A client of ours noticed that when creating a new Pop Up and saving the popup, the save button gets disabled and it does not save. While doing some debuging, I found out by disabling ACF Pro, the pop up saves correctly, so I narrowed down to the acf-input.min.js file. Currently, I have it to where if you're editing or adding a new pop up, I have dequeued and deregistered that file within the admin_enqueue_scripts action. This allows me to successfully save the popup.
The steps to reproduce this issue is as follows with ACF Pro activated:
1. Add new popup
2. Set a title
3. Add an image to the WYSIWYG area
4. Link the image to a page (this may not be required, but it's what the client is doing)
5. Save the Popup
Result: Does not save
I attached a youtube video of the issue as well --> https://www.youtube.com/watch?v=FXmkYEYDOkI
I updated ACF Pro to the latest version, but it still did not help the situation.
I have a vanilla install of wordpress with just ACF 5 Pro and Popup Pro as well, and the issue still persists.