It is sad how you're willing to misinterpret and overblow it, Alex. Collabora Office is a downstream (i.e. derived) project of LibreOffice, and although it is based on the same codebase, it may have its own bugs.
It is not fair for unpaid, volunteer triagers to spend time triaging their software's bugs in a bug tracking system pertaining to a different project, that is all. The NOTOURBUG status is meant to indicate that the bug simply needs to be moved to a more appropriate instance, as we do with e.g. snapcraft-related issues, which I triage on Launchpad.net. NOTOUTBUG does *not* mean that your bug is invalid. I am sorry because I am terse in my non-native languages, but really, there is no conspiracy behind it. I translate Collabora's software for free, but as you may note, they host their Weblate platform independently from TDF's -- their Jenkins is similarly separately hosted; their online help site is, too. For GOOD REASON. Adolfo