Edit: Now implemented in three of my skins:
Jupiter,
Mercury, and
Neptune. An example, from the demo albums:
https://jgromit.com/neptune/folders/
Plenty of options - float thumbnail left/right, align caption left/center/right, different caption width, etc.
It's also easy to force the thumbnails to be in only one column - just set the maximum thumbnail table width to be only about 200px larger than the width of a single thumbnail and its caption (the extra is needed for things like padding, top-of-page arrows, and so on).
ETA: In the demo album, if you want to play "shrink the browser window" to see what happens, hit F5 after changing sizes. At the lower end (i.e., smartphone size), the layout isn't redrawn dynamically. A desktop user isn't turning his browser into a smartphone while he's viewing the album, or vice-versa.
Edited by: jGromit on 29-Mar-2020 08:13