Strip tabs from sheets (PR #2062)

Match the styleguide

GitHub

You’ve signed the CLA, nschonni. Thank you! This pull request is ready for review.

We unfortunately do not accept style-only changes. cf. https://meta.discourse.org/t/where-does-discourse-stand-on-minor-refactoring-prs/6677

OK, I was trying to move it in line with the styleguide, but I’ll try and add some functional changes too