Better name for issue tracker or perhaps forums

"Bug Reports & Feature Requests"

I don't think anything will help. No matter how we try to make the name more explicit, users will still think "I'm having a problem, so this is a bug report" or "I can't see how to do this, so this is a feature request."

I agree with Isaac. Unfortunately, reading the forum instructions (or even just the description) appears to be too much for some people. The best solution I can think of would be to have the ability to reclassify an issue as a forum post (or vice versa) and to move posts between forum sections. The OP should have this ability for their own post, and perhaps a select group of trusted users would be able to do it to other people's posts. Maybe everyone could have the ability just like issue titles can be changed by anyone. URLs would not be affected because they are all of the form https://musescore.org/en/node/110561 so there would be no problems with broken links.

Well, I think it is confusing that we have a forum with the word "Bug Reports" in the name, and then when people use it to submit a bug, we tell people to go to the "Issue Tracker' instead. I'd propose simply removing "Bug Reports" from the name of the forum.

I also agree that when posting to the issue tracker, it would be good if the user was given more feedback about the purpose of the tracker and the existence of the support forum. Also, the meaning of the fields should be made more clear - people seldom "get" the Assigned field.

For the forum title "Support and bug reports" has a Dutch forum equivalent which translates (literally) back as "General Questions and problems".
Perhaps a combination of "Support and Problems" could be better suited?

As for the 'Assigned' field; what if it could only be changed by users that have signed the CLA? Those are likely to know what it means and are so far also the only candidates for actually fixing/implementing an issue.

I do very much like the idea of transforming issues to forum posts, and I think that it is a far more common thing than the other way around. Whether that should be available to all users or a more select moderator-like group? It depends on how easily it would be to transform items accidentally too imo.

I'm not sure making the forum topics more general will help users distinguish between them, so an ability to swap posts between forums is probably still necessary. I like jeetee's idea to use the CLA to decide moderator privileges.