Python Editor: Programmable Filter/Source script does not appear in editor when popout editor button clicked

Platform: macOS Version: 5.9.1-1838-ga289885f Qt Version: 5.15.1

Steps to reproduce:

• Start ParaView, builtin server
• Add Programmable Source
• Type some text in the Script text editor. Click the button to pop out the editor. This brings up the "ParaView Python Script Editor" with a tab ("New File"), but no tab with the text from the Script property
• Now, in the tab that is open, type some text. Save the file. After saving, you will see a new tab (also called "New File") with the content of the Programmable Filter/Source Script property. The original tab will still be called "New File" as well.