Long past time I reported this.
In DNA match list for A in a project/tree (this was MyHeritage but I seem tp recall it happening for others) selecting a match (B) and clicking on the URL for the match details to B - fine, you get the match details betwen A and B - as expected.
Then switch to a different MyHeritage kit in the same project/tree, C to see how they match B
Find the same match B
Click the URL for the match details C to B - and you get the match for A and B - bug
I tried fooling it to reset memory by selecting a different match (D) for C - turned out to be one on A’s list and took me to A/D instead of C/D.
Tried another who wasn’t on A’s match list (E) - fine, took me to C to E as hoped.
Then tried going back to C to B, still got A / B match - bug.