When hovering with the mouse over the projects/subprojects (left side) there is ‘drag’ icon in front of the project name which is supposed to symbolize that you can move it, isn’t it?
But I can’t drag and drop or move projects up/down at all here.
You should be able to change the order of the project, if you have
permission for it (if you don’t have permission, you should not see the
drag icon). If that does not work, can you reproduce it on the demo?
Did a few more tests and it works perfect when you didn’t set any color for your projects.
When projects have a color dot in front of the name dragging/moving isn’t possible anymore.
oh wow that sounds like a bug. Is it reproducible on the demo?
It is… or was!? Really strange, after I found this possible reason I deleted all the colors from my projects and was able to move/drag the projects 
But 10 minutes later I have the problem again - I can’t move/drag it anymore 
P.S.: Wright now for example I can’t move/drag the projects in the demo instance too. Really strange.
Small update:
I did my tests all with Vivaldi Browser (here I still have those mentioned problems).
Now I’ve tried it with MS Edge and voila it’s working there.
Does it work in a private tab in Vivaldi?
Since both browsers use the same rendering engine under the hood, that should not make a difference but you never know.
Bot chromium engine yes, I also tried it with vivaldi private tab but still the same (while it is still working in Edge)