Plasma 6.3.6-1 is in both Testing and Stable branches currently. Plasma 6.4.4-1 is in the Unstable branch.
You can choose to wait for it to reach Stable - it will be ready when it’s ready - or, you could switch to the Unstable branch to experience Plasma 6.4.4.
The bug report referenced;
This means they (KDE) are still waiting for information from you. Thus far, you have provided nothing that’s actually useful to them.
Interestingly, I’m aware of no other reports suggesting any issue such as you describe. I use KDE myself on several different OS and have not encountered it.
It’s very likely that what you are calling a “bug” is an issue limited to your own system; your own environment.
That being the case, I’d suggest you create a fresh new User account (for testing) to see if the issue(s) still occur, and then report back with the outcome.
In the meantime, please provide system information as described (below) as this might help to identify and rule out other possible contributors.
Regards.
Welcome to the Manjaro community
As a new or infrequent forum user, please take some time to familiarise yourself with Forum requirements, and the many ways to use the forum to your benefit:
Update Announcements
The Update Announcements contain important information and a Known Issues and Solutions section that should generally be checked before posting a request for support.
System Information
While information from *-fetch type apps might be fine for someone wishing to buy your computer, for Support purposes it’s better to ask your system directly; 
Output of the inxi command with appropriate parameters will achieve this (naturally, formatted according to forum guidelines) and will generally be more useful for those wishing to help:
inxi --filter --verbosity=8
or the short form:
inxi -zv8c0
- inxi man pages (Arch Manual)
Be prepared to provide output from other commands whenever asked. It’s equally important to provide as much actionable information as possible in your first post, rather than simply indicating there is a problem.