Signal package has Electron (which is built on top of Chromium and NodeJS) + Signal app code and assets. So not surprised that it’s bigger than Chromium.

Similar to maximize but it tries to expand the window only enough to show all the content without needing to scroll.

Although the functionality is still abysmal, you can also double click the title/header bar to zoom.

If you just want a separate session, container tabs will do. No need to create a new profile.

For Chrome, you can also just create a new profile.