If I am writing backend code I am mostly in a single IDE window moving tabs with code files to other screens is working but is inconvenient.

When I work on frontend I much rather have preview on second screen and most likely reference next to it.

When writing documentation or requirements I cannot imagine working on a single screen as essentially I am integrating multiple data sources into one, like I need to see how app looks now and before release, what changed and still have my working space for draft.

Switching windows to quickly look up documentation is fine but when creating requirements having time to understand what needs to be in which place how it has to evolve I need to have it right there so that my imagination doesn’t runaway.