Problems with Contextual Alternates

I’m experiencing some issues with a few combinations in the calt-feauture.
I took a screenshot to explain the problem, I hope it makes sense.
I’m running Glyphs 3.0.3 (3083) on MacOS Mojave 10.14.6

You forgot the ' after the C in the sub rule.

:persevere: Sorry, my bad…
The ‘t’-issue is still remaining, but only in Glyphs app, not after export :confused:

The ‘t’ sub looks good. Can you send me the file that I can have a look?

What’s the difference between t.alt01 and t.ss01.alt01?

Thanks for the file. This was a preview problem in Glyphs (I fixed it) and the final fonts are fine.

Thank you!