The screenshot element selector often does not allow the user to select certain elements that are the most useful ones (e.g. the main content region). These regions can be hovered over using the dev tools element picker, but not by the screenshot tool.
Repro:
Open any docs.rs page (e.g. https://docs.rs/ratatui/latest/ratatui/) and attempt to take a screenshot of just the main section with the content. Or open any github repo (e.g. https://github.com/ratatui-org/ratatui/) and attempt to take a screenshot of just the readme section.
Then Right click and inspect, click the pointer and look at the items available to select from by hovering around the screen.
Workaround: right click the particular node in the dev tools and then screenshot node.