If you launch google-chrome from a terminal window, you might get more useful output as to where the error is. It sounds like google-chrome is having problems spawning the KDE file-chooser.
[ugabrovec@office001 ~]$ google-chrome
Fontconfig warning: "/usr/share/fontconfig/conf.avail/05-reset-dirs-sample.conf", line 6: unknown element "reset-dirs"
[10590:10590:1106/201358.024958:ERROR:sandbox_linux.cc(369)] InitializeSandbox() called with multiple threads in process gpu-process.
[10590:10590:1106/201358.259395:ERROR:buffer_manager.cc(488)] [.DisplayCompositor]GL ERROR :GL_INVALID_OPERATION : glBufferData: <- error from previous GL co
mmand
[ugabrovec@office001 ~]$ XDG_CURRENT_DESKTOP=KDE google-chrome
Fontconfig warning: "/usr/share/fontconfig/conf.avail/05-reset-dirs-sample.conf", line 6: unknown element "reset-dirs"
[13867:13867:1106/202313.602851:ERROR:sandbox_linux.cc(369)] InitializeSandbox() called with multiple threads in process gpu-process.
[13867:13867:1106/202313.839038:ERROR:buffer_manager.cc(488)] [.DisplayCompositor]GL ERROR :GL_INVALID_OPERATION : glBufferData: <- error from previous GL command
[14058:1:1106/202316.403571:ERROR:child_process_sandbox_support_impl_linux.cc(81)] FontService unique font name matching request did not receive a response.
[14058:1:1106/202316.404165:ERROR:child_process_sandbox_support_impl_linux.cc(81)] FontService unique font name matching request did not receive a response.
Yeah, I can choose a file and all that, but then it’s all errors… FB, Gmail, second hand sales site etc. It all works fine in Firefox, is this some kind of Chrome issue?
Gmail gives me this: This file is 0 bytes, so it will not be attached.
FB: Oops Something went wrong. We're working on getting this fixed as soon as we can. You may be able to try again.
And the second hand sales site gives the familiar Chrome error: Aw, snap!
A quick way to do this might be to install chromium (dnf install chromium) and see if it has the same issues, since a fresh install of chromium should not have any extensions and should have the exact same behavior as google-chrome.
But I just noticed something else. There were no updates in the notification area for 2 or 3 days now, which I find interesting because usually there’s always, but literally always, updates. So I did sudo dnf upgrade --refresh and there are some updates. Let’s see that first.
Do you have any other WMs installed (besides KDE Plasma) where you could switch to temporarily just to see if the behavior persists?
I’m also wondering if this is something that didn’t quite get upgraded properly when you went from Fedora 30 to 31. It might be interesting to see what packages are on your system that don’t have the .fc31 dist tag: