[Feature Request] Allow Custom Templates to Sync Between Themes

[cat-og]

What

At the moment, all templates are intrinsically linked to theme on which they were created; including custom Templates. If a user chooses to change their theme, they lose all work created in the custom templates unless they manually copy the content over.

If we can't allow the Custom Templates to sync between theme changes, can we include a notice for users who have Custom Templates to inform them that their Custom Templates will not be transferred over?

Why

If a user changes their theme, they lose all content created in the custom templates without knowing why, or what has happened. This can be confusing or distressing in what should be a seamless process, and discourages theme changes.

How

No response

[mrfoxtalbot]

I totally get how this would be confusing, especially if you have added the content of your homepage to a template.

What happens if they switch back to the previous theme? Does the content come back?

Also, we should find a matching issue in core (or open one if there isn't any) Thanks again!

[annezazu]

Just noting that this matches this issue and effort in Core: WordPress/gutenberg#55595