P: Slow UI when using Mac and Custom Display Profile

@Rikk  Exactly my issue - 28"Samsung 4k monitor calibrated by i1 Profiler. Painfully slow - 2-3 sec to render each photo using custom profile, move Lightroom over to 2nd 1080p monitor and photos render immediately - even though it also has a custom calibration profile. Switching the 4k to sRGB speeds things up greatly, but not as fast as the 1080p - expected. Opening LR in low-res mode also helps even with custom profile.

OSX 10.14.6 with i7-3770, 16GB RAM, AMD RX580 8GB, photo library on external SSD through USB3. Internal drive also SSD on SATA6 bus.

mixed experience here:

MacPro6,1 macOS 10.14.6:

LR9 just fine

LR10 lags badly unless main display set to sRGB in System Preferences, no matter what LR hardware acceleration and preview settings

MacBookPro11,5 macOS 10.14.6:

LR9 and LR 10 just fine

I also have this problem ! I'll now use the Adobe RGB profile as substitute and this helps. 

iMac (Retina 5K, 27-inch, Late 2015)

3,2 GHz Quad-Core Intel Core i5

AMD Radeon R9 M380 2 GB

yes, but what colour profile are you now using? If that was reset to default, well.......

*celinezug il y'a deux solutions: ou bien retourner au version 9.4, ou bien utiliser le profile standard sRGB.  

Ou bien attendre....

Bill, whoever you are, I have LrC on 3 Macs of different generations and configurations, from quite old to very new, quite modest to powerful.  All run 9.4 (and Capture One 21) quite happily.

If I install LrC 10.x, then toggling between my custom profiles and sRGB toggles this bug like turning a light on and off.  Rikk has clearly admitted to this issue in his last update.

Was your son using custom profiles? If not, (a), I guess he's not that bothered about colour fidelity and (b) just shut up and go and spread disinformation on some other thread, rather than trolling people here who are already frustrated by this 3 month old showstopper they're paying for very month.

well, maybe, but one would think that the "A" team might be a bit concerned that the issue affect custom display profiles might not just go away with the migration to new hardware...

I also find Rikk's equating MacOS users who use custom display profiles with a "small group" a little complacent.

Much less expensive than "$10k Mac Pro". I probably read your response wrong, I thought you were saying that you were going to buy a $10K machine to run boot camp. Sorry. 

So... a "much less expensive solution" to free Bootcamp is costing $2000

"I think that Apple stopped supporting Windows in Bootcamp last year."

Apple announced they wouldn't support Bootcamp on ARM Macs, but I haven't seen any announcement they've stopped supporting Bootcamp on Intel Macs:

https://www.pcmag.com/news/arm-based-macs-wont-support-boot-camp-apple-confirms