I am currently having this same issue, I have removed all of the excess files in my custom behavior pack but do not have any way to use it on my realm. When accessing the menu I do not see it listed, but the pack works perfectly on my non-realm worlds. It looks like this thread didn't find a solution but here's hoping someone out there solved this.
Edit: Got the issue solved To fix it you literally need to just keep trying to upload it. I made this post initially after suffering for 40 minutes, after another 30 it finally showed up with no changes made on my end. If you have this issue just walk away for a bit and cross your fingers! It will work after a bit.
Emery Alspaugh
I am currently having this same issue, I have removed all of the excess files in my custom behavior pack but do not have any way to use it on my realm. When accessing the menu I do not see it listed, but the pack works perfectly on my non-realm worlds. It looks like this thread didn't find a solution but here's hoping someone out there solved this.
Edit: Got the issue solved
To fix it you literally need to just keep trying to upload it.
I made this post initially after suffering for 40 minutes, after another 30 it finally showed up with no changes made on my end. If you have this issue just walk away for a bit and cross your fingers! It will work after a bit.