I just had the same thing happen to me and I figured out why (at least for me).
When you check for and run update, it will update the launcher. To do this, it runs several git commands to checkout the latest from https://github.com/clockworkpi/launcher
One of those git commands is “git reset --hard $1”
Now if you are like me and reorganized your Menu by changing the ##_ prefixes, this will restore all the originals while leaving your new ones. This BREAKS the launcher. I haven’t gone through all of the launcher code, but it probably gets confused by the duplicates. For example if after the update you have 10_Settings and 90_Settings the launcher sees them both as “Settings” and breaks.
After removing all the duplicates caused by the update, launcher worked again.
Another thing to note, is that permission also can screw with launcher. I created a folder with “sudo mkdir” causing it to have root:root ownership and this also broke launcher making it stuck at “Loading…”.
Git should NOT be used as an update mechanism, and in this case, can be destructive as any changes you make to your launcher menu layout can be nuked and cause all sorts of problems like this simply by “updating” the launcher.