I'm building a UI with a side panel for navigation links. The content of the page would have a max-width while the sidebar stays fixed when scrolling the content. I'm not sure where to place the sidebar for widescreen displays.
Apps like Notion seem to pin it to the edge of the window regardless of the window width (image A below).
The WCAG site instead includes it within its content's max-width. I like how it makes the entire UI accessible within a reasonable width. It seems to work well for the WCAG site, since the sidebar looks like it's part of the content itself, and also scrolls with the content.