In a recent beta a regression was introduced that means the dashboard in most cases never finishes showing the loading worm.

You can see this as the little white strip at the top. The app works, and you can navigate, but it looks very very bad and may be symtomatic of other problems.

I know as of commit 7b7d2858e58caccd3b8e3d9f787bfb4f0c9ba103 this was not a problem.

It seems to be introduce in this commit:

1ba6c8edb0f3f5e1912bd6a0b1f842dd8e7690b0
ie:
https://github.com/jenkinsci/blueocean-plugin/commit/1ba6c8edb0f3f5e1912bd6a0b1f842dd8e7690b0

Some explanation by tfennelly:

"The <PageLoading> does not seem to be clicking into action on the pipelines page, with the result that the loading indicator just stays in a loading state forever, which looks a bit weird. I had a quick look at it but can't make any sense of it. Maybe someone else can.
Seems like PageLoading is not activated on the page at all and so the LoadingIndicator show and hide functions are never called. That's just from a quick scan though, so not really sure."