There is an add-on in Chrome called “Voice Clock” that automatically speaks the time every 30 minutes. This is great for keeping track of what time it is when you get engrossed in something.
Is there anything like that on Mozilla Firefox? If not, is there someone who could create it?
Thanks.
Deb
That’s a great question, @Deborah_Lefler! Would Alarms & Clock work?
You might also want to reach out to the developer of the Chrome extension “Voice Clock” and ask if they would be interested in porting their extension to Firefox. With the new WebExtensions API, porting should be possible and relatively painless. If you would like, you can include a link to the porting instructions to make it easy for them. 
https://developer.mozilla.org/Add-ons/WebExtensions/Porting_a_Google_Chrome_extension