Your comments

" try and simply "disable the addin" close the browser. Reboot your computer, Open Firefox and enable the addin FVD again. If you don't see your dials right away, then simply open a new tab as you would normally. It all depends how you had your dials configured [example: either have dials as your start/home page or only when you open a new tab etc.

It has largely to do with how you have your FVD customized."

This doesn't works.

So i saved my entire Firefox profile, uninstall Firefox, reinstalled Firefox 70.0.1, copy my saved Firefox profile and my Speed dial was here. OK. I uptated Firefox and ... my Speed dial disappears...

OK

I uninstalled Firefox, reinstalled Firefox 71, copy my saved Firefox profile and .... my Speed Dial disappears

OK

I uninstalled Firefox, réinstalled Firefox 70.0.1, installed FVD Speed dial From Mozilla, added some dials, closed Firefox, reopened it and my dials was here

OK

So I updated Firefox 70.0.1 to 71 and ... my Speed Dial disappears


So YES i think Firefox 71.0 has something to do with speeddials no longer working

why do you want to connect to my computer to fix a bug in Speed Dial ?