”Webpage is slowing down your browser” This is the new way the browser tells you there is a problem with the script program(s).
https://support.mozilla.org/en-US/kb/warning-unresponsive-script?cache=no

https://support.mozilla.org/en-US/kb/task-manager-tabs-or-extensions-are-slowing-firefox

After clicking on Wait several times, I find that closing down FF and restarting it generally gets rid of this issue.

I always run the most recent version of FF and I have it set to open with 7 tabs. Is there a setting to allow FF to run longer before it presents the A web page is slowing down your browser. What would you like to do? message?

Thanks,

John

I think there is, but I don't remember how.