Automatic width adjustment for flex0
fab css
Change stretch to flex-start
fab css
Revert "fab css"

This reverts commit a45a2c0f2ae26e7b731dc54965a6b224a39454b4.
Revert "Change stretch to flex-start"

This reverts commit 774073116dd4195037c452d48f05b432bba38801.
Align-start widget subarea
fab css
Merge pull request #5083 from minrk/one-nb-server

don't create js test directories unless they are being used
Updating JS tests README.md.
Merge pull request #5078 from ellisonbg/js-readme

Updating JS tests README.md
output_scroll can't be a vbox.
fab css
Updated alignment example.
Added align-start to widget container.
fab css
trust cells with no output

It's outputs we don't trust, so if there are no outputs there's nothing to distrust.
trust cells with no unsafe output

not just cells with no output
make sure the test notebook has some outputs to check
Fix incorrect usage of attrs