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Thank you!

Hello Fabian,

Does the screenshot make any sense?

It seems Thunderbrowse has options for this, but the "OK" button doesn't save them so I couldn't test them

Can you save the options you choose when going to Tools > Add-ons > Extensions > Thunderbrowse > Options > Tabs > TB3 Tabs[NM] (choose this radio-button) > OK ? Also take a few moments to carefully read all the options.

It seems it's a known bug in Thunderbrowse, I left a comment on the MozillaZine Forums (which is suggested to report such bugs in their FAQ) as well as a review on the Add-ons site.

I tried the last 5 previous versions of Thunderbrowse and they have the same problem which has also been mentioned by others in the forums.

The last version dates back almost two years, so I don't think it's likely there is going to be a fix. Perhaps you can also try contacting the author directly.