When opening /admin/plugins the plugin list/settings do not show. Only after a hard refresh, the plugin page loads correctly.
Build: 2.9.0.beta10 - (7718ef97cc)
I’ve seen something similar happening with the adplugin + an adblocker. Is this one of those situations?
If you do have the adplugin, does the same happen in an incognito browser?
Behavior is the same in incognito, also had adblocker whitelisted for my own domains anyway but was worth a shot. Does not happen on mobile btw, just desktop.
Checking the console:
Uncaught Error: There is no route named adminPlugins.houseAds
When I refresh, the console error pops up after loading the page for a while, but no settings will be loaded. On hard refresh the page loads fine. After a hard refresh, a normal refresh will result in not being able to load the page again.
This does sound like the adplugin + adblocker issue. Is there some way you can test this in a clean browser with no adblocker?
I disabled the plugin and it works perfectly now… strange that even whitelisting (aka disabling adblocker for a domain) did not help.
After enabling the adblocker again, it still works as expected… will see how it goes.
I was going to suggest disabling, but I saw you’d already tried safe mode and thought you’d need to uninstall it (which seemed a touch too far this early in the debugging 
). It’s good to know that disabling is useful for fault-finding. 
I am unsure why whitelisting hasn’t worked, as that’s another tip we’d offer as a workaround. 
I ruled out adblocker because of the safemode where it still didn’t work indeed. Maybe it was a bug in the adblocker 
But on another note I just did a test to see what I should see when safe mode is enabled now that the issue is solved, /plugins/ does not load in safe mode at all, even with adblocker disabled 
- so giving the exact same result as my screenshot above. Refreshing to exit safe mode works and plugins load instantly.
Ha. Yes, that does make a lot of sense. I’ve clearly not had enough cups of tea this morning.