Offshoot of JENKINS-33498: taking things a step further, it would be good to use dynamic column width for stage cells, permitting them to grow if screen width is available to better accomodate content.

As starting points:
https://github.com/jenkinsci/pipeline-stage-view-plugin/blob/master/ui/src/main/js/view/templates/pipeline-staged.less#L239
This sets the width of table cells (even if max-width is set, they don't grow).
This sets the overall width of the table cells in view, as does the line below it:
https://github.com/jenkinsci/pipeline-stage-view-plugin/blob/master/ui/src/main/js/view/templates/pipeline-staged.hbs#L4
Which is unfortunately hardcoded in JS to give 10em to each stage:
https://github.com/jenkinsci/pipeline-stage-view-plugin/blob/master/ui/src/main/js/view/pipeline-staged.js#L60