I've added a search filter (checkboxes) to my WP archive. It shows the checkboxes in the block editor. But the checkboxes are not shown on the front-end.
I swear I tried that... but you're correct it's working now.
However, I want these to just be checkboxes that filter with AJAX without a refresh. Do I have to have a submit button? I will not have a text field so it's just the checkboxes, and I'd prefer not to have a button.
I changed the settings to use AJAX without a page refresh, removed the button, and it works properly. So I guess the answer is I don't need a button. But then why did a button need to be added in order to get the filters to show up in the first place? Could you look into that, I'd consider it a bug.
This isn't a bug. It could perhaps have been something else but I stopped checking after I saw that it appears after.
I've seen cases where the theme would set this section to hidden on the frontend and resaving the view resolves the issue. In your case I cannot clearly defined exactly what happened given that it is now working consistently.