Backport #17375
Define unique names for image tabs in pull requests, in order to toggle tabs correctly when multiple are displayed on one page.
Fixes position of swipe-bar so it does not overlay other UI components when scrolling.
Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>
Co-authored-by: Mario Lubenka <mario.lubenka@googlemail.com>