I have read this sentence from some board and I have doubt about its meaning.
If you must use something other than Tails or Whonix, then only use the Tor Browser (and only for as long as it takes to download one of the above).
According to the bolded phrase, does it mean I should just only use Tor for downloading one or more of Tails and Whonix if I haven't installed Tails and Whonix?
Best Answer
The author really wants you to use either the Tails or the Whonix operating system to conduct whatever activities you wish to accomplish. And if you're using a different operating system, they are telling you it's OK to use Tor Browser on that operating system, but only to obtain Tails or Whonix.
They are saying you shouldn't use Tor Browser for any purpose on any other operating system except to obtain Tails or Whonix.