If there was no sign anywhere in Hong Kong on Sunday of masked protesters in black T-shirts, it was because the word went out to all to set November 24 aside for voting in the district council elections.Online platforms popular among protesters, including the Telegram messaging app and online forum LIHKG, shared messages telling everyone eligible to vote not to use their smartphones, dress in black, or wear masks inside polling stations to make sure their votes are valid.Regular protester Kevin…