jupyter lab suddenly slow to start up?

[Asterion Daedalus]

I have had an install of jupyter for some time.   I haven't upgraded or changed things up for ages.  Has worked fine for some time.   

Today it takes ages to start?  

So, where would I start looking to try to triage that style of problem please?

There was no chatter in the startup command line to hint that there were any problems.

Seems fine once start up, so far.

Cheers,

A