Hi extendsim, it's usually a Bitdefender setting. However, I don't see it under that name in the User Guide here: https://download.bitdefender.com/resources/media/materials/2019/userguides/en_EN/bitdefender_mac_2019_userguide_en.pdf?ver=1

Do you want to try to adjust the settings in BitDefender's "TrafficLight" extension in Firefox? You could try turning off features there any see whether that makes any difference, or disable it completely.

You can view, disable, and often configure or remove unwanted or unknown extensions on the Add-ons page. Either:

• Command+Shift+a (Windows: Ctrl+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then scan down the right side and click the extension's Preferences button (or Options button), or "More" link to see whether you can access its settings.

Any improvement?

Oh, page 17 of that manual says you can access the TrafficLight settings by clicking its icon on the toolbar, then Settings.

Perfect! I disabled the TrafficLight add-on in Firefox and have not seen this issue come back up! Thanks so much for your help!