Testing version: Panda
What were you doing: Inserting an image into Panda.
What feature did you use: I inserted the image using the image icon in the editor. It also happens if I drag and drop the image into Panda.
What happened: the file automatically saved to the file extension .textbundle and became a Ulysses file and defaulted to opening as a Ulysses file. I have the Ulysses app on my Mac.
What did you expect to happen: that the file would continue to default to Panda to open rather than having to go back and change the default application back to Panda to re-open the file.