I'm working on a little repo. I have branches master, m1, m2, m3, m4 and m5. I recently worked on m4, created a directory and committed my changes. Now I checkout m5, but that directory I just created on m4 is still there. Trying to understand why that might be and if/what I should do about it.
e.g.
PS C:\Repos\mystuff> git co m5
Switched to branch 'm5'
PS C:\Repos\mystuff> git ls-tree -r --name-only m5
.gitattributes
.gitignore
LICENSE
README.md
PS C:\Repos\mystuff> git st
On branch m5
nothing to commit, working tree clean
PS C:\Repos\mystuff> ls
    Directory: C:\Repos\mystuff>
Mode                LastWriteTime         Length Name
----                -------------         ------ ----
d-----       2019-09-14  11:02 AM                04   <== old folder from m4
-a----       2019-07-23   7:25 PM             66 .gitattributes
-a----       2019-09-03   7:58 PM           5980 .gitignore
-a----       2019-07-23   7:25 PM           1065 LICENSE
-a----       2019-07-23   7:25 PM             32 README.md
Why is that old folder still showing in ls, even though it is not in the files for the branch and doesn't show as untracked?
Can/should I (safely) deleted it without messing up m4?