I posted on Aug 7 that flushing caches fixed the issue, but it didn't last. ID locks up over and over every day opening the same suite of files for the same missing fonts. Switching font versions between projects is a part of my workflow. Missing fonts should not not cause minutes' worth lockup. I've deleted and reinstalled the fonts, InDesign, Creative Cloud. Nothing seems to fix it. I have to go offline to open files!

ID 17.3
OS 12.5.1

Same result in Windows 10 Pro, running InDesign version 17.3 x64
Almost unusable, when trying to Preflight files where the file creator doesn't understand the need for fonts, to accompany their job. Trying to switch between jobs that have missing fonts to jobs that contain all of the fonts, takes about a minute.
My InDesign file does contain Mac Type 1 Suitcase fonts, that are missing on my Windows platform. Not sure if the missig Mac Suitcase fonts make a difference, or if it's any missing font causing the problem.

For anyone still having this issue, I finally was able to fix it for my install. I'm not sure whether all of these steps are necessary, but I turned off Adobe font syncing in ID. In the CC app, I turned off all Adobe fonts. In the CC app File Syncing settings, I turned of the Adobe Fonts service. Repaired the CC app install. Then reversed the order. So far since then files open like lightning. Must have cleared out some malwritten code somewhere.

I have this issue as well, but it happens regardless of whether there are missing fonts or not. It seems to be worst on first open of a file in a given day/duration of time. Could it be connected to whether there are Postscript fonts in the file still?