Thumbnail info

When in LIBRARY mode, I would like to fill-in a title on the thumbnail frame. Howver, if I write the title in the "title"box in Lightroom, that text shows up in the breadcrumbs when viewing the large image. I would rather like to have the file name (without the extention) if at all possible. The way I found to do this, is to fill in the image title in the LABEL box in Lightroom. Like in the included image. The title is “Being at home with Claude”. On the album page, the large image displays the file name, but with the extention.
Capture d'écran_ 2026-04-09 à 14.07.27
As for the large image: https://pideja.ca/galleries/02_tnm/2014-2015/1-being-at-home/TNM140915-5904-single

Any suggestions?

I don’t see a filename extension on tha large image