Hi melonics, if you are using the about:debugging page to work with your extension, you can click the Inspect button to open a developer tools console where messages specific to your extension can appear. https://developer.mozilla.org/docs/Tools/about:debugging

Sometimes they are a bit cryptic...

The Add-ons team has a website to help with extension development questions over here:

https://discourse.mozilla.org/c/add-ons/development

Thank you for teaching.

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