The following reasoning was used for deciding to remove the "Page: " label, and replace it with a tooltip, from the main toolbar:
- We have no other visible labels in the *main* toolbar (e.g. the Zoom dropdown doesn't have a label, but only a tooltip).
- We already hide the "Page: " label when the viewer is narrow.
- The varying width of the "Page: " label in different locales is already causing issues for many languages, with overlap in the main toolbar as a result.
Trying to create responsive CSS styles that works well in all locales is already difficult, and if we add support for page labels that will only further compound the issues.
- Some PDF viewers (e.g. Adobe Reader, pdfium in Chrome) doesn't show labels in the UI by default.