Gnome freezes with many windows open

Without fail, after some time (2-10 minutes) watching a youtube video my graphics will freeze. The computer is completely unresponsive and I cannot change to an F3-F7 terminal.

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EDIT:

I realize now that with few windows open I can watch videos without causing my system to freeze. I was just editing a file with vi in a terminal, however, and my system froze. All I can think of is that many windows were open. I changed the title accordingly.
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I would write a bug report but I'm in the dark as to the cause of the problem and am not sure how to proceed with debugging. I'm posting this question here because I have the impression that the problem is graphics related.

My machine also has had trouble booting until I updated to the 4.20 mainline kernel, but I am not sure this is related:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1792100

Could someone help me to debug this or at least figure out which package to file a bug report against?
Thank you!

I'm using 18.10 with Wayland and Ubuntu Gnome3 with the following graphics card:

03:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Oland GL [FirePro W2100]