DiffText is too similar to Search

[asheq-svmx]

Is your feature request related to a problem? Please describe.
DiffText looks exact same as Search which can get really confusing

Describe the solution you'd like
Want DiffText highlight to be changed. I think it should be markedly different from other common highlights like Search. May be to something purple-y or blue-y.

Describe alternatives you've considered
I am able to override in my config to an (ugly) purple that I chose myself. But I would like someone with a professional eye to choose a color and benefit the entire user base.

Additional context
Here's the problem in a diff (invoked by git fugitive):

• The DiffText highlight is surrounding the vf (I added spacing around it).
• The Search higlight is sf (I search for sf using /)

Notice how it is super confusing at first glance because you don't know which is which without thinking and checking.

[ellisonleao]

moving this to the diff discussion