A very wary Weaver

I noticed this young female Hacklemesh Weaver crawling along the floor in the near the bathroom scales beside the toilet. All of a sudden, it stopped & raised it's front legs up which is a warning display with many spider species. I didn't think it was in response to my presence as they're usually very timid & I've never had one do that to me before. 
They usually stay close to their web tunnel & disappear quickly when faced with creatures much larger than themselves.
I thought it could have been due to her being caught out in the open.

Then I noticed a slight movement out of the corner of my eye & understanding dawned instantly.
AHHHHH-HA! The Weaver had touched a couple of the anchor lines of another spider's web!!!
The movement was a Cellar spider which had emerged from it's hiding place behind the top of the scales. It was very cautiously testing for vibrations while it slowly moved towards the Weaver.

It's stealthy approach didn't work though. Before it had covered even half the distance, the Weaver turned & bolted in the opposite direction.