I think you have a different definition of "open source" than I do at least. LGPL is (IMHO) a true open source license.

I agree though that some licensing changes would really help them grow. I think they've hurt long term adoption in exchange for short term revenue. I don't blame them, baby needs new shoes after all, but as a huge fan of Qt I would love to see them become a standard. The product is good enough that they deserve it, but the license can be a bit scary for people who aren't already familiar with it.

Qt's site does seem to be trying to scare you into believing that you can't possibly comply with the LGPL and you really really should buy the commercial license, for your own sake.

LGPL isn't really that onerous though..

However, new modules in Qt 6 and any rewrites of modules Qt 5-> 6are now GPL, which is rather copy-left and will spread to the rest of your code.

>However, new modules in Qt 6 and any rewrites of modules Qt 5-> 6are now GPL

That's very surprising, it would make upgrading from Qt 5 to Qt 6 a no-no for the small companies who use Qt LGPL. I'm sure they want to keep developer mindshare. Which LGPL Qt 5 modules became GPL in Qt 6?

caveat is that, quite a few pieces here and there are not LGPL, and it's not so easy for beginners to figure out how to do it the right way, I was one of them.

The "success" of others prove otherwise.

> charge premium for those who need your professional service to make profits

How exactly does that work? Why would the company invest a lot in the library if they can just offer professional services without it? For example, KDAB already offer professional services around Qt and do not need to spend much in R&D.

I believe GP is sarcasm for recent Red Hat situation

It's one of the most common UI libraries I've seen. It seems to work out well from them.