New Rule: detect properties conflict

[zallek]

Hi, It would be great to have a rule to detect properties conflicts.

Example:
The following would raise an error. As float: left has no effect on a flex item.

.comment {
  display: flex;
  float: left;
}

Would be great to find an exhaustive list of css properties conflicts.

[DanPurdy]

If you can find a list I'd be happy to look at it but I think the problem you will have is when using some of these as fallbacks.. I'm typing this on my phone but I think that would have an effect in ie8 for example..