We have a rule for our Garden species project. Only species recorded in, on, above or below our back garden footprint should be included in our species list. Technically we only ever saw this species in the garden when we opened our patio door, as we have only seen it once, hanging by a thread on the inside of the patio door frame and therefore it was only in the garden when we opened the door. But fairs fair and rules are rules and we welcomed it to our Garden.
According to ref 1 below, its main habitats are open woodland and heathland. The same reference material suggests there are no similar species.

We have read online that whilst it is common in some areas, it is rare in other parts of the country and for no obvious apparent reason. The following day it was gone from the door frame and we haven’t seen one since. The day before the above record we visited Rodney Stock National Nature reserve on the Mendip Hills and now wonder if perhaps it hitched a ride home with us, as we had spent time exploring the relict heathland and woodland of the area.
It will be interesting to see if it appears ever again.
Ref 1: Bee, L & Oxford G & Smith H. (2020) Britain’s Spiders: A field Guide. Second edition. Oxfordshire: Princeton University Press