This combination of parameters can be useful for displaying text in expanded form, which is not shown on the preview.
|Declined||None||T147184 <mapframe>: Remove empty div with thumbcaption class|
|Open||Arlolra||T51097 Use figure and figcaption HTML5 elements when possible|
|Open||None||T155375 Extract thumbframe etc from parser into EmbeddedContentRenderer|
|Open||None||T151703 <mapframe> with "text" and "frameless" parameters should not show frame|
I think the problem doesn't come from the frameless attribute, but rather from the text attribute, that gets used in a wrong way.
For graphs (see T147768#2773162) we revisited the text attributes to be such as this:
Graphs and Maps attributes should be consistent. Maps can have an additional text attribute for <maplink> only: the text displayed as the link.
Copy-pasting my comment in the RFC T148706