PSA: we just landed a commit on ecma262 which tweaks the formatting, which is the sort of thing which causes a lot of merge conflicts. if you have an in-flight PR and you're rebasing on main, you can avoid manually applying the formatting by using the following series of commands:

git rebase -i 0090daf^ # 0090daf is the commit where the formatter is applied
git rebase -X theirs 0090daf --exec "npm i && npm run format && git commit --amend -a --no-edit"
git rebase -i main

this splits up the rebase into 1) everything before the formatter was applied, 2) the formatter, which will be done for you, 3) everything after the formatter. any conflicts in parts 1 and 3 you will need to handle manually, just like you would in the absence of the formatter (or feel free to ask the editors for help)