Why do FOSS developers claim cross-platform support when their stuff is frequently broken on Windows in frustrating ways?

Two examples out of thousands I've countered: Bitcoin Core on Windows has a very annoying glitch which causes a cmd.exe (or similar) window to briefly appear and immediately go away, showing only for a fraction of a second, whenever a blocknotify or walletnotify signal is received (necessary to properly implement a payment system). This slowly but surely drives the computer user insane, to the point where it's impossible to keep using the machine if Bitcoin Core is to be running on it. (Which is crucial in my case.) Countless work-around commands for the directives were tested, and numerous attempts to talk with the developers were made, but they just claim that they don't have Windows and that it's "not a priority". The pg_dump command in PostgreSQL on Windows, used to backup a PG database, ignores the --exclude-table-data parameter of the table or schema name contains a "special" character, even though everything is correctly escaped and named (according to both Windows and PostgreSQL), and verified to work with other programs. Same thing here: they just basically claim that they have better things to do than to fix bugs on Windows, such as fixing bugs on Linux. The practical end result of this is that I'm forced to dump by database in its entirety, meaning my backups become hugely inflated with useless debug data. I could go on and on. I've numerous times had various scripts just assume that Linux is being run, calling Unix commands which are nonexistent on Windows. Reporting this always falls on deaf ears, but yet they keep on claiming that they produce "cross-platform" software instead of just being honest and saying that it's Linux-only software. Of course, I'm not saying that it's trivial to figure out all the madness that Microsoft is doing, but that's kind of... the point. If it were somehow "automatic" and a non-issue, everyone would obviously be running the exact same operating system and there would be no need for "cross-platform" software or any extra work. It's not like I'm sticking to Windows "out of spite" to make life hard for myself; you wouldn't believe how many times I've said "good bye" to Microsoft's harassments, angrily downloaded and installed a Linux distribution, only to realize that the open source community's toxicity actually *far surpasses* Microsoft's (rightfully called) horrible actions. Whereas on Windows, "only" 90% of my time is spent working around idiocy and downright sadism, in the case of Linux, it's over 99%. Basically nothing but problems, no matter what I'd try to do. And I'm genuinely happy for you if your experience is somehow completely different. The question is why they want to appear to support Windows when there are major issues with their releases for that platform which prevent them from being used correctly? You might answer: > They have limited time and resources. Patches/donations welcome. That may be true, but they keep working to release major new versions with entirely new features and whatnot all the time. What if they maybe slowed down a bit with all the new stuff and simply fixed the current bugs until they add more stuff? Is that really such an unreasonable stance? The exact same criticism ironically applied to Windows, especially with their ever-changing Windows 10. There are so many bugs which are just left untouched for year after year, as they keep piling on more unwanted garbage. But in their case, it's financially motivated, whereas these open source projects are free of charge and they should be able to take as much time as they feel necessary to make their existing feature-set solid and robust before even thinking about adding new features. I just don't understand the mentality.