Tab Mix Plus doesn't remember my settings... (in Off-topic)

Every time I restart Firefox Tab Mix Plus seems to have forgotten the settings I saved...

Anyone have an idea to help against this?

I'd like to let it remember not to put the 'New Tab' button and keep my tabs the same size (so I can read the title of it) instead of merely an icon...

I don't know what causes your problem. It would be good if you make sure both your browser and extensions are up to date. There is also another possibility, if you installed more than one extension related to one aspect of your browser, there might happen a conflict (they call it incompatibility) between two or more extensions.

If you have another extension dealing with tabs, and they have at least similar function, you need to make sure both extensions doesn't conflict one or another. One extension's settings might override another, or might bring unexpected result.

Btw, have you tried reinstall Tab Mix Plus?

Both the extension and the Firefox install are brand new and up to date.
I haven't installed any other tab browsing plug in which would conflict with it.

I also have checked a re install of the tab mix plus which didn't help alas...

Have you configured Tab Mix Plus via the Tools -> Tab Mix Plus Options Menu to do what you are wanting it to do by default?

Yes, this is why I find it so frustrating / strange why it doesn't work...

Strange, got an update from Firefox and all is well now :)

did you have Firefox set to delete cookies everytime you close the browser?

nope :)