Windows 10 Pro, 64-bit OS.

GUI bugs. They happen most of the time.

They are present in RC.4, but not in master.

• Bug 1:
  To reproduce:

1. On the master mixer channel, double-click it or right-click it then select "Rename channel".
   The green border of the naming box isn't there.
   
2. Click anywhere in the mixer other than the channel itself.
3. Do step 1 again then press enter.
   The name of the channel is highlighted in gray as if it was selected.
   

While bug 1 is present in a project then opening a new project, the bug will be present in it.

This bug can't be undone unless LMMS is closed.

• Bug 2:
  To reproduce:

1. Add a mixer channel if there isn't one.
2. Do step 1 in bug 1.
   The green border of the naming box isn't there, too.
3. Click any mixer channel other than the master one.
   

While bug 2 is present in a project then opening a new project, the name of the channel in the new project will be the same as the old project like this:

This bug can be undone by doing step 1 in bug 1, but this will result in bug 1.