2022-10-21: I saw this ad after visiting a couple of accounts, related to nuclear power stations. Notice Hunter Biden and Adam Schiff in the picture.
Twitter bans Americans from posting “political ads”, but allows the Russian government to post ads that might be intended for spy recruitment. The screenshot shows an ad from RosAtom, Russian government nuclear agency.
The screenshot has been made today, November 21, 2019, in Texas. The RosAtom ad is in Who to follow section, highlighted. This ad doesn’t even allow the user to check why s/he sees it.
Also, read about Big Tech in Skolkovo.