Tab is broken
I set my tabs to 4 and “Replace by space” (default) and everything else uses the default. If you make a new line then hit “home” to go the beginning then “Tab”, it spaces over an arbitrary number of columns. But if, after creating a new line, you hit Shift/Tab to get to “home” subsequent tabs work properly.
can you give us additional infos?
Which npp version, which os, using which theme, have you plugins installed,
and an example to reproduce it?
I tried with a new document and do not have the reported behaviour.