P: Camera Raw/Lightroom Classic/Lightroom Ecosystem: Support for WebP

Good suggestion, @johnrellis. Thanks! 

For everyone: if you are interested in following his suggestion, here is how to do it using Google WebpTools. 

Please note: the solution works for Windows only, as we need to create and use a DOS batch file. This DOS batch file will be executed after each of your EXPORT actions, and it will create a .WEBP converted version of your images in the same folder you exported the .JPEG one. 

1) download the Goole WebpTools and extract the zip file in a folder. Please extract the files in a folder that you are not going to change, otherwise the batch we are going to build in a few moments will need adjustments.

To simplify the explanation, I will assume that you extracted the files in a folder C:\WEBP, which therefore should contain the subfolders BIN, INCLUDE, LIB and the other files included in the Webp zip file.

The important thing is that in C:\WEBP\BIN you should have the CWEBP.EXE file. 

2) in C:\WEBP, create a new text file calling it CONVERT.BAT. Right click on it and select EDIT (with Windows 11, after right clicking you will first need to select "Show More Options" to see the EDIT menu item).
The file is normally opened with Notepad. 

3) simply copy in Notepad the following batch command, and then save the file. 

FOR %%x IN (%*) DO C:\WEBP\BIN\CWEBP.EXE -q 85 %%x -o "%%~dx%%~px%%~nx.webp"

What does it do? Well: the EXPORT feature of Lightroom will call this batch file passing him ALL the path of the images we have exported, one after one. 

And the FOR... DO loop will execute, for each of them, the CWEBP.EXE command, converting each image in WEBP format, and saving it in the same folder as the original image. 

The "85" you see is the QUALITY of the conversion. If you want a different quality, simply change that value. 

The strange %%~dx%%~px%%~nx.webp is used to remove from the path of the image the file extension (i.e. I need to get rid of ".JPEG"). As you can see, I am appending the ".WEBP" extension to it.

4) Now, let's configure Lightroom so that it executes that batch after each JPEG export. I think you already created a custom EXPORT Preset in Lightroom to export your images as JPEG, right? Otherwise please first create a JPEG export preset in Lightroom, a simple one is enought. 

Now in Lightroom go to FILE menu, then select "EXPORT...", left click on your preset, on the right part of the form go to the bottom section "Post processing", and in After Export select the "Open in Other Application..." option. 

Then click on "Choose..." button and browse to C:\WEBP, selecting the CONVERT.BAT we've just created.

IMPORTANT: before clicking on DONE, don't forget to RIGHT CLICK on your preset (in the left "Preset:" listbox) and select "Update with current settings", otherwise your recent changes to the preset will be lost.

Now you can click on "DONE". 

You're done.

To verify that everything is set correctly, reopen FILE\EXPORT..., select your preset, and verify in "Post-Procssing" that you see "Open in Other application" in After Export, and you see "C:\WEBP\BIN\CONVERT.BAT" in the "Application". 

Now you can select your images in Lightroom and then select the EXPORT preset we've just modified.
In the export folder, you will find both .JPEG and WEBP files. 

If you want to see what the CONVERT.BAT does, please simply add a PAUSE at the end of the CONVERT.BAT file.
Like this: 

FOR %%x IN (%*) DO C:\WEBP\BIN\CWEBP.EXE -q 85 %%x -o "%%~dx%%~px%%~nx.webp"
PAUSE

The batch will pause after the execution, so that you can read the information in the DOS screen where CWEBP is executed. Simply type ENTER and the DOS screen will close.

I hope it'll be helpful for you! Thanks again @johnrellis for suggesting that, I've never realized there was a "post processing" feature in the Export presets!

Bye,

A.-