

4 to 5 added like 2 tags, but was fully backwards compatibile. the painful upgrade you’re thinking of was 3 to 4 where they basically rewrote, it but don’t have any tutorial content other than one of the main devs making an absurdly long series of walkthrough videos so it’s impossible to find the topic you’re interested in
most things seem to have settled on this, but tabs are so much better for accessibility. programmers with bad vision can have trouble differentiating smaller indentation levels, while some of them just bump the font size up so high that 4 spaces takes up too much screen space. each one can set a tab width that is comfortable for them. https://alexandersandberg.com/articles/default-to-tabs-instead-of-spaces-for-an-accessible-first-environment/ has some good arguments
with a forced formatter and a configured editor there really isn’t any argument for spaces