Filepicker - No valid focus target found

Hello,

When a user accesses to the filepicker and then closes it, the focus is not set on the button that opened the dialog.
The console log said "moodle-core-widget-focusafterhide: No valid focus target found - not returning focus."

Is it possible to fix it ?

How can I patch it by myself while waiting for a better solution ?

Thank's

 
Steps to reproduce:

• Create a new Assignment module
• Using the keyboard to tab through the form, enter a title, then open the file manager and select a file.
• Tab to "Upload this file" button and press enter.
• Expected: The file manager is closed, and focus returns to the button that opened it.
• Actual: The file manager is closed, and focus is moved to the top of the page.