In the last years, I have seen plenty of users telling or promoting certain ultra-permissive rules as part of Open Source but which are not even in the definition like the use of read-only licenses, being a good example the MEGA software.
However, I didn’t find exact source of these ideas and only believed in the misinformation of certain videos in *tube or similar.
Today, I was looking for a FLOSS VPN client to use at home as I use MATE DE and found Printunl Client promoted as Open Source. Or that was everything until I read the license.
Yes I was really into Vivaldi for the vertical tabs and ditched them after I heard their pathetic reason for not being open source, yet building on top of open source.
You are aware that you can get vertical tabs in Firefox, too, right?
Tree-Style Tabs is the most popular extension for that: https://addons.mozilla.org/en-GB/firefox/addon/tree-style-tab/
Tab Center Reborn is also neat (no tree-structure, but thumbnails): https://addons.mozilla.org/en-GB/firefox/addon/tabcenter-reborn/
I had to abandoned Firefox due to a really horrific response issue (despite clearing caches etc) - I have about 20 tabs open per browser and it was slowing really badly obviously due to one or two of those tabs chewing up resources. But yes I certainly used its vertical tabs along with Vivaldi (until I discovered Vivaldi’s abuse of open source).