Sometimes, I don’t want the panel users to care about the title of an existing page. I know I can set the title field in the page’s blueprint to be readonly, but I would like to completely hide the field in the panel. I can’t just get rid of the field, because Kirby needs a title field in the blueprint of a page to work correctly. I tried giving the title field in the page blueprint the type: hidden, but that doesn’t work.
I just want the page title to exist in the content text files, but don’t show up in the panel. That way, the title would be set when the page is created and could only be changed afterwards throw the filesystem, and not throw the panel.
As you say: Kirby needs the title field and it is used everywhere in the Panel: When creating pages, in the sidebar and on the edit page itself. I think that it especially makes sense to keep the title field (also on the edit page) so that users can set a title for the sidebar, even if it is used nowhere else.
What is your specific use-case?
While I totally agree with @lukasbestle that this isn’t something I would recommend doing at all, you could use a custom stylesheet for the panel to achieve this: http://getkirby.com/docs/cheatsheet/options/panel.stylesheet
And then use a rule like (I’m pretty sure there is a nicer selector, just as an example):
.form > fieldset > .field:first-child {
display: none;
}