everhelper sync in Firefox not working, creates duplicates, that then get spread to the other browsers.

Hello

Please check article - https://nimbusweb.me/s/share/3872564/rd5n866176c9czqv0iun

That makes no difference.  

Chrome ) Sync fine.

Opera ) Sync fine

Edge ) Sync fine

Vivaldi) Sync fine

Brave ) Sync fine

FireFox ) Will not sync, without first being told to merge, upload or download.  I've already done that.  Everytime I do one of those 3 things, it screws the system up.

Do you see any sync error?

There is no sync error, because it never tries to sync.

Every day I'm researching why.

I believe it has to do with FireFox not allowing autologin.

every other browser, once logged in, it stay logged in, even if I close the browser and reopen the browser.

That means, after I initially made my choice on your sync page.

'Merge' 'Upload' 'Download'

Then I don't have to make this choice again.

When I open FireFox, do some work, then go to sync my book mark changes. I have to make that choice, again.  Everytime!!

That means if I made changes on 2 different browsers, one of them gets wiped out.

This tells me, it's not your fault, but I can see FireFox has no intention of changing, so I'm hoping you will find a way to just allow my to hit sync, without having to choose

'Merge' 'Upload' 'Download'

first.

I hope my rambling response made some sense.

Hmm, did you change any privacy settings in Firefox?

no, I can't get any site to open automatically in FireFox, even my google GMail.  In researching this, it seems that it is intentional on FireFox, as a security measure.