Open explorer URL in same Firefox instance new Tab

[jetspeedz]

nothing special in profiles.ini

[General]
StartWithLastProfile=1

[Profile0]
Name=default
IsRelative=1
Path=Profiles/z12mn42r.default
Default=1

[Brummelchen]

And installs.in?

[jetspeedz]

Problem Solved, I'm surprised no one thought to tell me to check this.

Tools>Options>General>Open links in tabs instead of new windows = Make sure this is checked

It was that simple, sadly it took me half the day by messing with files between old profile and new one to narrow down the delta between profiles to figure out it was in the pref.js file which this option causes this issue.

What I don't quite understand is why this option changed, I certainly didn't change it, somewhere between the updates 66>68 this was no longer checked. In any case, close this thread.

[jscher2000]

Problem Solved, I'm surprised no one thought to tell me to check this.

Tools>Options>General>Open links in tabs instead of new windows = Make sure this is checked

I think because there was a Firefox 67 issue with opening external links in a new profile, no one asked whether "new instance" simply meant a new window of the same profile, which was how we all understood it before Firefox 67.