[tin-bugs] string question

[Joe Dalton]

Hi I'm translating to Danish and have a short question regarding one of the strings

It is this string
#: src/lang.c:367
msgid "toggle tabwidth 4 <-> 8"
msgstr "slå indrykningsbredde 4 <-> 8 til/fra"

what is exactly meant by 4 <-> 8 here

Is it at change from 4 to 8 which toggles tabwidth from 4 to 8 spaces back and forth or
is it more a name for at mode "4 <-> 8" which is different from the standard (so different tabwidth in different circumstances, which is then collectively changed here).

bye
Joe