Custom page with sidebar under page title

Ops, I failed to copy the second snippet, I copied yours and not mine.
In the first snippet I wrote __before_main_container. And I wrote that because of your request:

I need to create a custom page template to put the (right) sidebar next to the content with the page header running across both of them at the top.

And yes it put the heading inside the main-wrapper container.

You changed it to “__before_main_wrapper”.

Don’t know why it didn’t work in your custom page template, to me works (both with __before_main_wrapper and __before_main_container). But I cannot see your code so.. cannot say anything.

Also, add an action to the hook __before_main_wrapper if you assign a priority (all except 10) works also in functions.php . And about that, I have to admit that I don’t understand why ??