Three Documents Freezing

[keithconover]

In a now-locked discussion a couple of months ago (https://community.adobe.com/t5/indesign-discussions/one-document-freezing/m-p/14157822#M545863), I posted about a document freezing on me. Thanks to everyone who answered my post, there was lots of good information in there, and I learned a lot. However, none of the suggestions fixed my problem.

After several weeks of being away from my PC workstation that can handle big InDesign files, I'm back at it. I now have not one but three files that lock up InDesign as soon as I type another word. (InDesign 19.0.1 x64 Windows 11 current patch.) As noted in that previous post, this PC has all the RAM and processing power one might need.

I have finally realized that (1) I've been putting in so many cross-references that it eventually makes InDesign choke. This is not a problem with a corrupt file, it's a problem with (a) me putting in too many cross-references, (b) me making too-big InDesign files, and (c) InDesign not being able to handle more than a certain amount of RAM and then going into disk-swapping lockup: not likely to be fixed any time soon. (I've seen evidence of that disk-swapping in Task Manager.)

My goal is to produce PDF files (and eventually to use IN5 or something else to make a website). Here is the current structure of the book, with each Volume being a separate InDesign file. I've got all of the Volumes in a single Book Panel. Here's the current outline:

Appalachian Search and Rescue

Foreword

Preface

Volume I: Survival

Chapter 1: Short-Term Survival: 1-58

Chapter 2: The Environment: 59-142

Chapter 3: Wilderness Travel : 143-160

Chapter 4: Equipment and Supplies 161-260

Chapter 5: Health and Fitness 261-276

Chapter 6: Wilderness First Aid (part 1/2) 277-484

Volume II: Ways and Means

Chapter 7: Communications

Chapter 8: Land Navigation

Chapter 9: Leadership and Followership

Volume III: Search

Chapter 10: Search Tactics

Chapter 11: Incident Management

Chapter 12: Search Theory and Strategy

Volume IV: Rescue

Chapter 13: Nontechnical & Improvised Evacs 1-40

Chapter 14: Wilderness First Aid (part 2/2) 41-96

Chapter 15: Knots and Ropework 97-296

Chapter 16: Rescue Management 297-306

After locking up this third file (Volume IV: Rescue), I've come to the realization that each Volume should probably be a Book Panel, with each chapter as a separate file. But then (wailing and pulling of hair and gnashing of teeth) what is going to become of all my beautiful cross-references? The ones that make the resulting PDFs so useful to readers? The file that just locked up on me (Volume IV) has on the order. of 300-400 cross-references!

Any advice on how to divide up these Volume files into separate chapters – and as much as possible preserving the cross-references – would be greatly appreciated.

[BobLevine]

InDesign is not the right tool for creating a website. Look into WordPress, Web Flow, or Square Space.

[keithconover]

Yeah, I know. Thinking about using WordPress but then dropping in bits output from IN5. But the primary goal is to produce a (free, online) PDF ebook textbook.

If you'd like to see the drafts of what I was able to produce so far, with their many cross-references, check out: http://www.conovers.org/ftp/AppSAR-Drafts. Now that I have run head-on into the brick wall of InDesign's inability to address more than about 1.4 GB or RAM without getting into a diskswapping lockup I will not be able to update these until I fix the issue. (We will not mention my creating massive files with profligate use of cross-references.)

In case someone is creating a large volume with separate chapters as a single InDesign file, though not as large or cross-reference-filled as mine, and wants to export individual chapters as PDFs but with the intra-chapter cross-references working as PDF links, and the PDF bookmarks from your Table of Contents intact and usable for navigation, with all of the bookmarks collapsed to serve as Table of Contents (sorry for the runon sentence) here is my procedure for doing so reflected in the individual chapters:

Pre-PDF check of volume:
Search for character style Hyperlink and check to make sure links are OK, just checking internal hyperlinks.
Then, go to the Hyperlinks Panel and check all the external links.

To create separate chapters, do it from within InDesign: File > Adobe PDF Presets > Small with Links > Save [will prompt for pages] >
• AppSAR-1-Short-Term-Survival: 1-58
• AppSAR-2-The-Environment: 59-142
• AppSAR-3-Wilderness-Travel: 143-160
• AppSAR-4-Equipment&Supplies: 161-258
• AppSAR-5-Health&Fitness: 259-274
• AppSAR-6-Wilderness-First-Aid-1: 275-484

AppSAR PDF Post-Processing for each volume and chapter (new Acrobat interface 2023):
• While chapter still open in Acrobat:
• Click on right top-ish bookmarks icon
• Highlight each chapter bookmark and press the "/" key to collapse all bookmarks in the chapter. Repeat this for each chapter. Save PDF via Save As > [save over original version]

(I had first tried the following but it failed in that none of the cross-references worked):
• Extract pages for each chapter, name as AppSAR-1-Short-Term-Survival or similar: open thumbnails panel (right, four squares > right-click any page icon > extract pages > type in the following: 
o AppSAR-1- Short-Term-Survival: 1-58
o AppSAR-2-The-Environment: 59-142
o AppSAR-3-Wilderness-Travel: 143-160
o AppSAR-4-Equipment&Supplies: 161-258
o AppSAR-5-Health&Fitness: 259-274
o AppSAR-6-Wilderness-First-Aid-1: 275-484

[keithconover]

First, let me say that I have no expectation that this textbook will ever be printed on paper. I want people to be able to download either chapters (smaller) or volumes (easier to link between chapters but larger) and view them as a PDF ebook.

Some more information, and a plan for going forwards in case you run into the same problem.

This lockup is related to the .indd file size. The three that lock up on me as soon as I start typing are:

28.1 MB, 151 MB and 197 MB. So, size factors in there, but more likely complexity is the issue. The computational overhead for cross-references likely does not increase linearly but more likely something like exponentially.

My workaround for this – still working on it – is to have all of the chapters as separate .indd files but be parts of a Book Panel (although in may case the "book" is going to be one volume of the entire book). Heretofore, I'd mostly used a book panel to synchronized styles across the book (a feature to be treasured). Now, though, I'm going to use the volume's book panel to produce the PDF files. Again, I have lots of cross-references between the chapters in a volume, but not between volumes, so that might work out OK.

Cross-references will not update automatically between .indd chapter files, but you can update them via the book panel. I cut out the first two of the six chapters in Volume I and saved them separately. I was able to use the Volume I book panel's top-right "hamburger menu" to access the "Update All Cross-Refernences" menu item, and then the hamburger-menu "Export to PDF" menu item to create a single PDF of the two chapters. PDF links between the chapters worked fine, and it didn't take any time for the "Update All Cross-References" to work before I made the PDF. Of course, I am concerned about that after I add the remaining four chapters! Breaking Volume I down into six separate chapters, I went to the Hamburger Menu > Book Page Numbering Options and clicked on "Continue on next odd page" rado button and the clicked the checkbox for "Automatically Update Page & Section Numbers."

In the Volume I book panel, I also used my mouse to highlight each of the two chapters, one at a time, and in the hamburger menu, setting the Section Prefix for Chapter 1 to be "1–" (that's a one followed by an N-dash, which I had to copy from an N-dash I had in InDesign) and "2–" for Chapter 2. I also clicked the checkbox for "Include Prefix when Numbering Pages." This seems to work well.

Once I get all six chapters into shape and in the book panel and export to PDF (or at least try to) I will report my findings.

[BobLevine]

That's not a lot of pages and a single file should be just fine. You're adding a bigtime level of complexity doing it as a book instead of a single document. 

For freezing, I'd export the docs as IDML and also check for font issues as well as any third-party plugins.

[keithconover]

Bob, I had already done that, several times, for each document. Failed. Good thought though, I have used that fix for other (smaller and less-complex) documents that seemed corrupted, and it worked.

[Peter34634266nm8j]

I would recommend wordpress to you as it is more user-friendly 

[keithconover]

The facts that I have one WordPress site and help maintain another also will make it easier <g>.

[keithconover]

This is NOT SOLVED as my primary aim is not a website, but a PDF ebook! (Actually individual chapter PDF ebooks.) I am still having great difficulties figuring out what is going on. I am focusing on the smallest of my lockup files, an early draft of a communications chapter. It is only 28.3 MB. The exported PDF is only 2.04 MB. Both are available for anyone to download in http://www.conovers.org/ftp/InDesign-Lockups/. Preflight shows no errors. Package shows no errors, though it does note that Marlett is an incomplete font (duh). But if I type more than a word into this InDesign file, it locks up. Of interest, I saw somewhere online that doing a Save As clears some cruft out of an InDesign file. Indeed, this helped. I was able to type almost two more sentences into the file before it locks up InDesign. I thought maybe that I linked too many .psd files? But what I found online said that it's better to link .psd files than the alternatives. I thought maybe someone smarter than me might glean some insight from what Task Manager looks like when InDesign is locked up:

When InDesign is not locked up, it looks almost the same except that (a) CPU usage is lower, and (b) there is no disk swapping:

I'm suspecting the problem is with the cross-references, and indeed, I found a lot of good cross-references (as you can tell from the slider bar in the screenshot below, there are  lot) but a whole page of corrupted ones:

So, next I'm going to focus on cleaning up the cross-references. Not sure how those corrupted ones got in there, but my next task is to go through and clean up all the cross-references.

[keithconover]

Those corrupted cross-references were due to my changing a New Hyperlink Destination's text and deleting the bookmark. Fixing this did not solve the problem. As documented in https://community.adobe.com/t5/indesign-discussions/cascading-book-panels-multiple-book-panels-for-a... I have now (laboriously) broken each volume down into separate chapters, with some side benefits as well.

After I ran head-on into the brick wall of InDesign's inability to address more than about 1.4 GB or RAM without getting into a diskswapping lockup I am now creating separate chapters with each volume as an InDesign Book Panel (book file in Adobe-ese).

In case someone is creating a large volume with separate chapters as a single InDesign file, though not as large or cross-reference-filled as mine, and wants to export individual chapters as PDFs but with the intra-chapter cross-references working as PDF links, and the PDF bookmarks from your Table of Contents intact and usable for navigation, with all of the bookmarks collapsed to serve as Table of Contents (sorry for the runon sentence) here is my procedure for doing so reflected in the individual chapters:

Pre-PDF check of volume:
Search for character style Hyperlink and check to make sure links are OK, just checking internal hyperlinks.
Then, go to the Hyperlinks Panel and check all the external links.

To create separate chapters, do it from within InDesign: File > Adobe PDF Presets > Small with Links > Save [will prompt for pages so I noted down the pages] >
• AppSAR-1-Short-Term-Survival: 1-58
• AppSAR-2-The-Environment: 59-142
• AppSAR-3-Wilderness-Travel: 143-160
• AppSAR-4-Equipment&Supplies: 161-258
• AppSAR-5-Health&Fitness: 259-274
• AppSAR-6-Wilderness-First-Aid-1: 275-484

AppSAR PDF Post-Processing for each volume and chapter (new Acrobat interface 2023):
• While chapter still open in Acrobat:
• Click on right top-ish bookmarks icon
• Highlight each chapter bookmark and press the "/" key to collapse all bookmarks in the chapter. Repeat this for each chapter. Save PDF via Save As > [save over original version]

(I had first tried the following but it failed in that none of the cross-references worked):
• Extract pages for each chapter, name as AppSAR-1-Short-Term-Survival or similar: open thumbnails panel (right, four squares > right-click any page icon > extract pages > type in the following: 
o AppSAR-1- Short-Term-Survival: 1-58
o AppSAR-2-The-Environment: 59-142
o AppSAR-3-Wilderness-Travel: 143-160
o AppSAR-4-Equipment&Supplies: 161-258
o AppSAR-5-Health&Fitness: 259-274
o AppSAR-6-Wilderness-First-Aid-1: 275-484

[keithconover]

My breaking my single-volume .indd files seems to be working, at least for Volume I. The "Save a Copy" and "Save As" and saving over the same name seems to be working to clean out cruft and keep the file size smaller.

There is one chapter from Volume IV that I separated out, and just finished going through and making sure all of the cross-links are OK. I had accidentally deleted a couple of Text Anchors and had to put them in, and a couple of URLs needed to be fixed. There are two URLs that show as red, but that's because they are paywalled, which I figure is OK if I'm referencing something that is paywalled. 

Unfortunately, it's doing the same lockup thing even if I edit it by itself: locking up as soon as I type one letter too many. 

After the first time it did this, I rebooted my PC with having set "chkdsk C: /f /r" to run with the next reboot. I then ran InDesign, had some problems with it crashing on startup as it tried to restore some files from previous crashes. Eventually, by clicking to tell it to not try to restore any files from previous crashes, I was able to load the file in question, save it out as an .idml file, open that, and then save it as an .indd file and start editing it again.

However, I was in the middle of typing the phrase "hanging by one hand" when it locked up. The InDesign screen looks like this:

When I move the mouse across the InDesign screen, the mouse cursor is invisible. I can Alt+Tab to see a miniature of the screen, but when I stop the Alt-Tab highlight on this screen, it doesn't show the full InDesign screen, it only shows the desktop or some of the other active programs. The only way to show this screen is to minimize all other windows. Right-clicking from the Taskbar offers me the "close" option, but selecting it does not close InDesign.

If I look in Task Manager, this is what I see:

And if I right-click the top "Adobe InDesign" and select "End task," this is what I see:

When I click "OK" then I am presented with two more error dialog boxes, exactly the same, after which InDesign closes.

The file that is causing this is online at http://www.conovers.org/ftp/AppSAR-Source-Files/ and the direct link is http://www.conovers.org/ftp/AppSAR-Source-Files/AppSAR-15-Knots&Ropework.indd.

Any thoughts on how to fix or avoid these lockups would be greatly appreciated. If I can get this project done it will probably save a few lives.

Thank you.

[keithconover]

Unlike the problem reported in https://community.adobe.com/t5/indesign-discussions/quot-populating-style-packs-quot/m-p/14424016#M5... this file was not corrupted, and I was able to load it without crashing InDesign. I am now in the process of splitting this into two smaller chapters. Still don't know what is the proximate cause of the lockups, obviously something to do with size. However, I have been able to do extensive edits on one of the two smaller chapters without InDesign 19.2 complaining a bit. I still have to rejigger all of the cross-references now that they span two chapters instead of one. To do this I should first create a book file and add the chapters to this, and have the chapters paginated with chapter number, N-dash and page number like I did for Volume I. However, that is corrupting the files in Volume I so I am not going to do so until my scheduled 2-hour conversation with senior Adobe tech support tomorrow. But this lends credence to the idea that there is a soft limit on the size of InDesign files. I say "soft" because it's probably a combination of the amount of text, number of styles, number of cross-references, number of linked graphics, and who knows what all else. For the chapter that I had to split, it was 92.5 MB and had about 300 cross-references, sometimes 4-5 to the same text anchor. It had about 125 linked graphics, about 3/4 of which were to .psd files (the rest .jpg or .png). So, taken together, that's enough to lock up InDesign 19.2. It won't corrupt your files, but if your file is getting up to this big, it would be best to break it in half. Since this has happened to me with four different .indd files at about the same level of size/complexity, this is not a one-off but a reproducible pattern, and with three different versions of InDesign, so not likely to change in the near future.

[keithconover]

After fighting with the Adobe support chatbot and the entry-level Adobe support tech as described in https://community.adobe.com/t5/indesign-discussions/quot-populating-style-packs-quot/m-p/14424016#M5... I had one of the best technical support experiences I've ever had, with a senior Adobe support tech. (And I've been having to deal with tech support since before Windows, before DOS, and back in the CP/M days with doing assembler programming.) She "read the room" and quickly adjusted to my level of knowledge, quickly understood the problems, and worked hand-in-hand with me to deal with both the "Populating Style Packs" thread linked above, and with this issue as well. She pointed out that it might be possible to get past that limit I noted by disabling that CEP html engine that kept spawning processes. She noted it's a legacy process that is not needed for what I'm doing, and pointed me at this thread on the forum: https://community.adobe.com/t5/creative-cloud-desktop-discussions/how-to-turn-off-cep-html-engine-pe... which then points to this Adobe support page: https://helpx.adobe.com/x-productkb/global/high_cpu_usage_cephtmlengine.html. I followed the instructions there, mostly. I had to open InDesign and open a file in InDesign to get the offending CEPHtmlEngine.exe to be visible in Task Manager. Rather than using ^c to copy the entire line in the expanded view of Task Manager with the Command Line column added, and then having to parse it, I found it easier just to look at the command line for CEPHtmlEngine.exe, which is my case was "C:\Program Files\Adobe\Adobe InDesign 2024\Resources\CEP\CEPHtmlEngine\CEPHtmlEngine.exe" and navigate in File Explorer to the folder "C:\Program\Files\Adobe\Adobe InDesign 2024\Resources\CEP\CEPHtmlEngine." I then closed InDesign. I then backed up that folder (backup in this case means "copy it to somewhere else"; I just put the copy in C:\bak which is where I put stuff like this) and then deleted the original folder. (Actually, instead of Windows File Explorer, I used Directory Opus which is a just wonderful replacement for Windows File Explorer. I have used it for more than a decade. The best part is being able to access online folders by FTP and manipulate them within Directory Opus just like another folder.) I then rebooted my PC. Now, when I open that really big file, I can add lots of text without InDesign freezing. However, I still see an hourglass from time to time, and I've decided for multiple reasons to keep my chapters smaller, mostly because they should be right-sized, not for technical reasons, but because that way they make a better textbook.

[MAURICE5EDC]

Hi Keith,

Did you wind up making the Web version with In5? If so please post your experience here. It'll be very interesting to know how well In5 handles a file or files like yours.

Maurice

[keithconover]

I'm just now working through some more major lockups with InDesign. It'll be a few months before I try IN5 with this big project but I will post what I find out about it in this thread. Thanks for your interest!

[keithconover]

As a follow-up, I have broken up my big chapter into six separate chapters within a volume for which I have an InDesign Book File (.indb). I have made sure all of the links, hyperlinks and cross-references are OK in all six chapters.

<digression> For doing repetitive things like updating the cross-references to work between the chapters, I found InDesign's facility to apply color and a bit of extra spacing to frequently-used menu items a terrific idea. I'm a UX dweeb and I love this, makes InDesign much easier to use for such repetitive tasks; your eyes and mouse cursor automatically move to the right place: much faster and much less error-prone. For repetitive tasks like that, I'd really like to assign the menu option to a keystroke, but not all menu items can be assigned to a keystroke.  And the menu highlighting means I don't have to change input modes: no "mouse > keyboard > mouse." And with the colored menu items, mousing is probably as fast and easy as using the keyboard.</digression>

I am now using InDesign 19.4. Performance with one of my larger chapters (but much smaller than my original chapter that was having problems, the one that is now six separate chapters I can only type a letter every 1-2 seconds. And when I typed a sentence in an ASCII programmer's editor (UltraEdit) and pasted plain text, InDesign froze. I then went back to try things to improve InDesign's performance and get back to editing the chapter. I tried:

• Getting rid of the CEP html engine (keeps reinstalling itself with updates to InDesign: see https://helpx.adobe.com/x-productkb/global/high_cpu_usage_cephtmlengine.html. Here is my slightly-updated version: Task Manager > [second-from bottom icon in left icon bar: Details] > [If Command Line column not showing > Right-click top row > Select Columns > Command Line > OK] > scroll to one of the lines starting with CEPHtmlEngine.exe > in File Explorer (or my favorite Windows utility, Directory Opus), navigate to the containing folder in its Command Line column (C:\Program Files\Adobe\Adobe InDesign 2024\Resources\
  for me; can just copy this and paste into Directory Opus) > Ceate a folder "bak" and move the entire CEP folder into it. Reboot.
• Got rid of some startup cruft that I could see in Task Manager, but none of it was that bad, and it seemed to have no effect on InDesign.
• Exported the file to an .idml file and then loaded to recreate the .indd file

Nonetheless, none of this helped, and after pasting a line of plain text into the file, it froze for 10 minutes and I had to use Task Manager to close InDesign. Sigh. The file is 63.9 MB and I guess that's just more than InDesign 19.4 can handle. Another chapter that's 59.2 MB I can still edit.

I wonder if changing my .psd files to some other format might help this? Using the File > Package menu option, this is the summary of the file:

Or maybe there's something else I can do rather than stripping out graphics or breaking this chapter in two.

When I'm actually packaging, I get this error:

If anyone would like to check out the chapter it's at http://www.conovers.org/ftp/AppSAR-Source-Files/AppSAR-6-Wilderness-First-Aid-1.indd.

It's a bit messed up in the Allergy and Anaphylaxis section I was trying to edit. I added a bogus H1 heading below where I was trying to type to see if it would help. Nope.

Sigh.

[leo.r]

I saw recently several threads when users complain that InDesign crashes when pasting text (or typing). Here's one (although no solution there):

https://community.adobe.com/t5/indesign-discussions/indesign-closes-after-copy-paste/m-p/14615193

As a test, try to revert to InDesign 19.3 - will it make a difference? It did help to some users with unusual issues. You can do this from Creative Clous app:

[keithconover]

Thanks for the thought, Leo. I did revert to 19.3 but pasting an ASCII text sentence into that file locked up InDesign hard. As before, in Task Manager I can see InDesign locked in a disk-swapping loop; memory's maxed at 1.2 GB and there is continual 2 MB/second disk swapping. Sigh.

[MAURICE5EDC]

Hi Keith if it's not too much trouble I would look at re-importing some of your psd files as jpg, or if you need transparency, png. There's so much more to a PSD that InDesign is aware of that I have to think it would at least not hurt to change the format.

I wonder if changing my .psd files to some other format might help this?

[keithconover · Accepted solution]

Thank you, Maurice, I suspected this might be the case. So I tested with a big file with lots of linked .psd files, one that was giving my lots of problems on my desktop PC. I opened it on my laptop (traveling now) and it took about thirty seconds to load, with the cursor alternating every half second or so between an arrow and a whirling blue circle.

I had initially imported .jpg files into .psd files to clean them up in Photoshop. For each, I had both the original .jpg file and the cleaned-up .psd file in my folder. I decided I didn't need to keep the original .jpg file, as it was effectively embedded in the .psd file for safekeeping. So I planned to open up each .psd file in Photoshop, then export to .jpg, overwriting the original .jpg. Sounded like a lot of work, but needed to be done.

I went through the folder of graphics. When I right-clicked the first .psd file and was about ready to, from the context menu, click "Edit" to open in Photoshop, lo and behold there was a context-menu item that said "Convert to JPG." I clicked that and in less than a second I was able to overwrite the original .jpg file with a new one that had all of the Photoshop tweaks. No options for JPG compression or size.  But, it was the right size and quality I would have picked. It only took a half-second to do this for each .psd file. Wow.

I have no idea where this context menu functionality came from. It could be from Adobe, it could be from Microsoft, or it could be from Directory Opus, the Windows File Explorer replacement I have used and loved for many years.

When I went through the links panel and changed the link for each .psd file to the corresponding .jpg file, and then closed and reopened the file? It opened in about a second and scrolling, which had been laggy, was quite fast.

Bottom line: changing linked .psd files to .jpg files can have a major effect on the performance of InDesign when that file is open.

[MAURICE5EDC]

Hey that's great Keith, glad it worked out!

A couple of thoughts for the next time you need to do this--there are plenty of ways to do conversions like this as a batch operation. I like the Image Processor script in Photoshop. Also, in the ID Links panel there's a option in the flyout menu called Relink File Extension which would let you change all the psd links to jpg in one go.

[keithconover]

While there may be ways to automate this export, I decided to do it manually via the right-click method; a few .psd files needed to be exported to PNG to preserve transparency, which I could also do in a second with the right-click context menu "Convert to PNG" which likewise worked well.

[keithconover]

Thank you, Maurice, I suspected this might be the case. So I tested with a big file with lots of linked .psd files, one that was giving my lots of problems on my desktop PC. I opened it on my laptop (traveling now) and it took about thirty seconds to load, with the cursor alternating every half second or so between an arrow and a whirling blue circle.

I had initially imported .jpg files into .psd files to clean them up in Photoshop. For each, I had both the original .jpg file and the cleaned-up .psd file in my folder. I decided I didn't need to keep the original .jpg file, as it was effectively embedded in the .psd file for safekeeping. So I planned to open up each .psd file in Photoshop, then export to .jpg, overwriting the original .jpg. Sounded like a lot of work, but needed to be done.

I went through the folder of graphics. When I right-clicked the first .psd file and was about ready to, from the context menu, click "Edit" to open in Photoshop, lo and behold there was a context-menu item that said "Convert to JPG." I clicked that and in less than a second I was able to overwrite the original .jpg file with a new one that had all of the Photoshop tweaks. No options for JPG compression or size.  But, it was the right size and quality I would have picked. It only took a half-second to do this for each .psd file. Wow.

I have no idea where this context menu functionality came from. It could be from Adobe, it could be from Microsoft, or it could be from Directory Opus, the Windows File Explorer replacement I have used and loved for many years.

When I went through the links panel and changed the link for each .psd file to the corresponding .jpg file, and then closed and reopened the file? It opened in about a second and scrolling, which had been laggy, was quite fast.

Bottom line: changing linked .psd files to .jpg files can have a major effect on the performance of InDesign when that file is open.

****** Addendum: After updating to 19.4, which seems a much better release in many ways, I had a couple of very-large files, with lots of linked .psd files, that would not open in InDesign 19.4 without locking up. That's even if I loaded the .idml file to create a new .indd file. Solution: went through most but not all of my linked .psd graphics, converted to .jpg, and then moved the .psd files to a temporary sub-folder so that InDesign couldn't find them. That way, the file opened without crashing InDesign, and I was then able to relink with the .jpg version and after this I can edit the file like normal.