The 'phantom auto deletion' is still happening in online version of Sketchup

I found this topic: “My work gets deleted when I select it” while searching about the same bug I was experiencing with the free online version of Sketchup just today. The topic was closed, but the bug is still happening. He was using Windows 10. Me, I’m using Debian Linux.
The exact problem is: Every 10 seconds (just 10 seconds, not less, not more) all selected or under active hover objects get deleted (just like having a 10 seconds periodic hammer hitting the Delete key)

That sounds about some internal Sketchup function performing some task every 10 seconds, but performs a “delete” instead.

The problem appeared after 2 days using Sketchup normally and then got persistent. It does not disappear by restarting the browser (Firefox) or disabling its plugins.
Cannot use Sketchup in this “mode”.