$ wget -q -O- https://ton.twimg.com/dataproducts/dist/bundle-dda40477bb495d7fee76.js
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https://github.com/hayamiz/twittering-mode seems to work without doing an app, perhaps t takes advantage of features that require the app? There may be no real answer here since no one likely wants to reverse engineer all that js. But its worth letting people know that twitter dev site requires running a nonfree program, not a nice thing to do.
The README says go to https://apps.twitter.com/app/new
Which is just a nonfree javascript program:
https://github.com/hayamiz/twittering-mode seems to work without doing an app, perhaps t takes advantage of features that require the app? There may be no real answer here since no one likely wants to reverse engineer all that js. But its worth letting people know that twitter dev site requires running a nonfree program, not a nice thing to do.