Star color accessibility for color-vision impaired users

[despens]

Hello all, my color vision is impaired ("strong protan" or "red-green-blindness") and am unable to distinguish the starred and non-starred tasks. It would be good to switch to an accessible color pair for selected and non-selected states (with a clear brightness difference), or work with a star that is just an outline when not selected and filled when selected.

I cannot make out the differences here:

(BTW using a color picker I just realized there is even a third star color present in this screenshot, impossible to distinguish for me.)

The yellow star clearly stands out for me here:

[raimund-schluessler]

We use three colors for showing different priorities, and gray if no priority is assigned.

• High priority: #B3312D -> red
• Medium priority: #FFDD00 -> yellow
• Low priority: #4271A6 -> Blue
• No priority: color of the main text -> gray

Using an outlined star if no priority is assigned would be easy enough. We could simply use this for example https://materialdesignicons.com/icon/star-outline

However, for the colors I don't really know how to solve this well. We would need a color set well accessible for color-vision impaired users. But I am afraid this would look a bit weird for users with normal color-vision. @nextcloud/designers Is there any input from your side? Do we have/want a nextcloud wide setting similar to the dark theme or high contrast mode for color-vision impaired users?

[stefan-niedermann]

Related to https://github.com/nextcloud/news-android/issues/1009 (and maybe contains some inspiration)

[despens]

There is no need to use a special mode for color-vision impaired users if the design is made to only use color to support indication instead of color being the main way of indication. There are many ways to solve this, for instance by using several stars to indicate different levels of importance (the usual "1-5 stars"), writing out the state of importance in words, using different star sizes users can cycle through via a clicking on them, etc. The current design also is not so helpful for users that can clearly distinguish all colors, because the colors do not communicate a hierarchy: is blue more important than green, or yellow? So there's a chance to address that problem as well.

[raimund-schluessler]

if the design is made to only use color to support indication instead of color being the main way of indication.

In the sidebar that is already the case, we write out the priority:

In the future, we plan to reduce the possible levels to four and show the respective number of stars, see https://github.com/nextcloud/tasks/issues/1128. However, for the task list this is not an option, I think, since the space is limited. We show limit the priority display to a single icon, otherwise it will simply use to much space. So we need another idea here.