[Browser] improve borderless aboutbrowser

[glitch128]

When the option "Borderless Aboutbrowser" is enabled, the invisible title bar covers half of the tab strip horizontally and almost entirely covers the close tab and new tab buttons. The way that I would fix this, if I knew how to, would be:

1. Make the app not an iframe, but structured like how the setting app is made.
2. Remove the title, and create the window controls as a part of the browser.
3. Make the background part of the tab strip the dragabble portion.

[velzie]

i don't think you really understand how it's set up. we are aware of the issues

[wearrrrr]

Gonna be fr, this is not what github issues are for. Use the discussion tab.