Scenario:

• I have multiple tabs open with "permanently loseable" content - once the tab is closed or refreshed, some information will be permanently lost. (For example, a Youtube page showing comments that have since been deleted.) I already know this specific content will not show up in, say, the Wayback Machine.
• While on a different tab, I left the machine idle for a while and then came back to see an "Unresponsive script" dialog. Thinking this belonged to the current tab, I pressed "Stop script".
• It turns out the script was something belonging to the browser itself. Now that whole browser window seems to have gotten into an unexpected state. I can hover over the tabs and they will light up as if switchable, but nothing happens on click. The back/forward/new tab/etc. buttons do that as well. If I right-click, the drop-down menu appears but all of the options do nothing.
• I can open new windows which behave correctly, but there does not seem to be a way to recover the other window's tabs from here. I can drag tabs between working windows but not the hung window. The "Switch to Tab" function also does not work.

I am trying to recover the contents of the hung tabs, but I do not know where to begin. Alternatively, something to force the stopped script to restart would also work. Unfortunately, I do not remember anything about the name of the stopped script or any details from the dismissed "Unresponsive script" dialog. The OS is Ubuntu.