If the current window (view and text panes) appears to not reflect recent changes made by the user, the UI can be force-refreshed by clicking the current tab. In default macOS settings, this tab will be highlighted in light blue. Or, if the user has customised their host Mac's OS, the highlight colour chosen in the OS.
By design intent of the app, this should not be needed, but this feature works around the occasional issue were a change in one part of the document (either the UI or underlying data) does not cause the UI to change as expected.
On clicking the tab, both view and text panes are completely re-drawn. When clicking avoid the 'x' and 'i' icons but otherwise anywhere in the tab, including the tab's textual label is fine.
If the text label of the tab briefly shows in red text, this simply implies the refresh work is ongoing. Such may occur, for instance if refreshing a very complex map with lots of links or images.