Twitter is one of several new participants (Medium and SoundCloud are among the others) in the July 12 internet "day of action" on preserving net neutrality rules, according to Fight for the Future.
Twitter joins big names like Amazon, Netflix and Reddit who have said they support the protest.
They are pushing back on FCC chairman Ajit Pai's proposal to roll back Title II and rethink the 2015 Open Internet order's rules against blocking, throttling and paid prioritization.
Backers of the day of action say the FCC is out to "destroy" net neutrality and give "big cable companies" control over what we see and do online.
Actually, the rules apply to broadband providers, which include cable companies but also telcos, wired and wireless.
Fight for the Future pointed Thursday to a Morning Consult/Politico poll finding a majority of respondents support prohibiting blocking and throttling and paid prioritization.
ISPs have long said they can live with no blocking or throttling, though they are somewhat less emphatic about no prioritizing. What they say they can't live with, or certainly don't want to, is what they say are Title II regs meant for last-century telephone service applied to this century broadband.