To avoid flooding another thread with unrelated posts about VCL quality and bugs, I have opened this topic for discussion about VCL in general and VCL Styles.   First, I would like to respond to comment made by @Attila Kovacs     VCL is not abandoned, not even close. Maybe it is not receiving too many new features as people would hope so, but it has more to do with its maturity than anything else. FMX (is) was in frenzy development cycle, only because it didn't have the needed features VCL already had, and it still does not have all. So it may have seemed that FMX is getting all the love and attention, but that was not the case.   Many new Windows related features introduced since FMX has come to play, are still VCL only.  Keep in mind that IDE is based on VCL, and I don't see that changing in foreseeable future. VCL is evolving and it will continue to evolve. It is not that FMX is new better, improved framework mean to replace VCL for all purposes, it is framework with completely different architecture and it covers different use cases. While some functionality certainly overlaps, and there are (Windows only) applications where both VCL and FMX can be chosen, there are also applications where VCL is far better (and sometimes, even only viable) choice.
VCL Styles are buggy, they have been buggy since they were introduced in XE2. But, they are now part of the IDE. That means two things. First, IDE is now suffering from some bugs, but it also means that those bugs will get fixed sooner rather than later. Unfortunately, not all bugs can be solved overnight, and the more specific, reproducible bug reports there are, the higher are chances that those bugs will get a fix. If you have any filed VCL bug reports you might want to share, please do so.