Bug:
While working in another program and letting this run idle, I came back to a "new company emerging" event filling the screen--but no matter how many times I clicked the button to continue, it was not doing anything visible (i.e., it was no dismissing the even notification screen). It did seem to continue to save my game, however, and upon fully reloading the page, I only had to go back to a save point from 53 seconds prior.
However, I was letting it idle to build up some iron to build more research centres, but it did seem to "freeze time" while the event notice was on screen as I did not see much of an increase in my iron stores from idling (about an hour's worth). Note that this IS the preferred behaviour, as I wold rather have time frozen at the event than to come back to my empire in flames because I was not siting here to deal with he event! Also note that some events do not seem to do this; Some events will post an "event over" screen which is "on top" of the "event begins" screen, so when I click to continue, it shows the event begins after I dismissed the event over... A little disorientating until I realized what was happening.
I am using Debian Linux v10.3+ (64-bit), Firefox 78.3.0esr (64-bit), which also has NoScript running (but currently disabled as many Steam apps seem to consider NoScript an "ad blocker" and refuse to run).
I cannot provide more information than this as the reload reset my current page load state.