Frameless buttons should have same minimum desktop click target sizes – `32px` as `em` calculation result` as framed buttons per default. This has been part of M101 since the original button definitions and makes sense both from layout certainty perspective (developers know what they can expect when start using a button and usability (incl. increased usability on mobile devices).
There are several use cases of frameless buttons, with only three implementations to my knowledge, where a smaller size is currently needed:
| Use case | 32px min-height possible? | Current size
| FieldsetLayout help icons, which are a unique case and would cause layout issues in refactoring. | {icon exclamation-triangle color=yellow} | 24px, this should probably also get bigger, but needs more design thinking upfront
| VE: Insert paragraph | {icon exclamation-triangle color=yellow} | 24px. Screen real estate is highly-valued in the edit context, would probably resist to change that. Should remain special case.
| VE: Transclusion dialog sidebar options | {icon exclamation-triangle color=yellow} | 24px, could probably be increased to 32px
| [[ https://doc.wikimedia.org/oojs-ui/master/demos/#widgets-mediawiki-ltr-desktop | Indicator-only frameless button ]] | | 12px; IMO no useful interface element currently, we should get rid of those anyway, see T150071
| Echo: markAsReadButton | {icon check color=green} | 30x30px
| Echo: mw-echo-ui-notificationItemWidget-content-actions-button | {icon check color=green} | 24px height, similar to standalone below
| Standalone frameless buttons (demo etc.) | {icon check color=green} | 24px height, width label-dependent – **those and the next ones are the most important to align height with framed buttons**
| Frameless buttons in horizontal layout | {icon check color=green} | 24px
Related to T110565