I've found documents that indicate the Simple cache is used by chrome on android. My testing shows it's also used on MacOS and linux. Chrome, Edge and Opera on Windows all use Block cache for me.
I've tested with Chrome 128 on MacOS and Linux(Ubuntu) and Chromium 128 on Linux(Ubuntu). All three use Simple cache and work with the experimental FFF code change.
Ideally, I'd like to test with older browser versions, to see when it changed and allow for back compat. But Google deliberately makes it as difficult as possible to downgrade to an older version. There might have been
another user with this issue last month.
I've spent the morning failing to find the details of this chrome change. At this point, I give up. I might try to make it configurable just for peace of mind since it's release time in a few days.