Edit: This seems to be because those are mapped to F14/F15 respectively in macOS by default. Apparently an non-Apple external keyboard cannot send Apples media keys, so unless your keyboard has its own media keys it will not work.
The Kinesis Advantage supports enabling media keys by pressing =n (see http://superuser.com/a/403765)
It's mostly for use with IntelliJ's IDEs, but it's been a real productivity boost for me. Will definitely be checking this out as a replacement.
If you're looking for more customization, there's always Karabiner (or Karabiner Elements for the latest version of macOS), but that is a hefty piece of software. This is great for when I do not need that level of configuration. Well done.
Thats exactly was I was looking for.
> Some of fntoggle's code was used. As its author wrote it could be released under the GPL2 license.
Then Fluor also needs to be released under a GPL license, doesn't it? See https://www.tldrlegal.com/l/gpl2
edit: Oh, this app isn't about the Touch Bar! It's about toggling the functionality of the regular function keys between F1, F2, etc... and their media/shortcut labels.