I know this isn't easy, but it shouldn't also be easy to see your child orphaned. It's been 2 years you don't publish any new public versions.
It seems now that GDrive had changed its URL or something, and viewing backups got broken. New changes will come that require fixes, and I fear some day TO will go inoperable.
That is summed to the years-old issue of the licensing tool, that only works on Chrome. You've been forcing us into Chrome for years. We wanna move to Vivaldi and Brave, but must remain on Chrome.
The sad fact is that browsers extensions isn't a profitable business. Few ppl buy extensions for browsers that are free. I'd pay a subscription, but even fewer would. And charging once for a lifetime license isn't sustainable.
A few months ago Sandboxie was made freeware, and its owner is promising to open its source. I had also bought its lifetime license and used its features for years, and now they are free for anybody, and we lost our support and will need to hope an open source community to rise and support it.
This is also sad and hard, but it's still better than have a software we love and use everyday, and which we bought, to die like that.
Don't let this happen. There's no other tabs manager nearly as good as yours. We bought it, we supported you. Many of us are willing to subscribe if that brings your hard work back. If you can't, or you think we're not numbered enough to bother, then just open the source so we can hope somebody else can take it.
See ClassicShell in example.
Customer support service by UserEcho