I just tried this out and it's very nice and easy to use. Thank you for sharing!
I ended up copy-pasting the output from the messages page, which is 99% of the way to exporting a .txt file and my personal use case. Great work.
In my videography work I often do a separate audio-only interview to use as voice-over for the final video. I like to print out a transcript, mark the highlights, then go to the sound file and extract the snippets I liked. Extracting the snippets is a lot easier when I have timestamps printed out inline with the text at intervals of one or two minutes. In the case of bigWav, there were timestamps marked at only three or four points, so I had to go back and manually enter ten more marks to orient myself on the page. In addition, I used ChatGPT on an answer-by-answer basis to clean up the copy and add in punctuation for ease of reading. So there was an hour or two of data sanitizing needed to get everything ready to print out and use efficiently.
What do you typically do with the text on export? E.g. Do you parse the times?