This is something that comes a very long way already, and I can even find someone else complaining about it. Wonder why I'm the only one that finds this super irritating.

Senario: 
How to see: (do any of these)

• Login (without popups and default login)
• Goto Settings of any page , module
• Goto any page where a control (ctl) is loaded. (where ctl is in querystring)

The problem:

1. All paneds is empty, except the default pane.
2. The control is loaded into the default pane, and all other panes in made empty and other controls not loaded,
3. I can understand why this is done, because you force some control to load onto a page, and the other pre-existing control is therefore "out-of-order".
4. BUT, now you website looks realy stupid..... you footers (settings - include on all pages) are now all gone !!!
5. Most (99%) of all skins I used before (and that it 100's from the days of DNN5) usually look silly when there are no content inside a page (height of whole page). The footers float like in the middle of the page, therea re whitespace below footers etc. As soon as you fill in content that expand ther page creater than the window, then all comes right.
6. So now you create this beautiful site, but when you login, or use anything that has ctl in the URL, then its just your headers, navigation and the default content pane with the one control in it. EVERYTHING ELSE IS GONE, You now have a super silly looking page, a blank footer, with just the terms and copyright notices, lots of whitespace, etc.

I can not believe everyone is happy for this for all these years!

Here is what I recommend should happen:

• If a module is set to "Show on all pages" it should show on all pages (does not matter what!!)
• Except when Settings: Show Popups = true

Workarounds:
This is some workarounds I used before, but is not that suitable.

1. Create a resx file for you skin, and modify your skin to incluse some stuff in some areas (like your footer). Then it will always be there.
2. Create a custom login page (at least your login pages does not look like half a page with have the content stripped out). The other ctl pages still an issues.
3. Use popups for everything..... then your changes to end up with a half stipped page is less.