Why did the highlight color change?

Previously, the lines I highlighted were a nice teal color.
One day they started to appear light blue. And now they’re yellow.
I haven’t been able to find a reason for this change or a way to set the highlight color in preferences.
Is there a way to do this? If not, what is the basis for the highlight color?

Thanks!

Edit: Also referenced here: https://github.com/WorldBrain/Memex/issues/1193

Hello @carmen.se, There is no memex setting to change the highlight color easily, but if you are on Firefox, I have found out a workaround. It’s fairly easy.
Please read the answer here : Solution.
Hope this helps !