Changed files are no longer highlighted in the editor tab bar. I updated from v1.23 on Gentoo.
Which desktop are you using?
Those items are now coloured according to styles in the geany.gtkrc file so they can be changed. This is because of a complaint from a colour blind user that they could not tell the difference between red and black.
It would appear that your desktop is not properly applying the styles.
The file geany.gtkrc is missing in the 1.24 tarball. As a workaround, you can download it from https://github.com/geany/geany/raw/master/data/geany.gtkrc and move to geany system data dir.
Putting geany.gtkrc in /usr/share/geany fixed the issue. Thanks!
Fixed in [157b44f443557f05543a9f4d05322ef1f4f24903], thanks.