Actual Behavior:
When using md-highlight-text, the resulting highlight isn't actually highlighting anything. At least the contrast is so low, that hardly any effect is visible.

CodePen (or steps to reproduce the issue): *
You can observe the problem directly at https://material.angularjs.org/HEAD/demo/autocomplete
Additional Information:
Chrome stable, Windows
Looks like the example from the spec uses something close to #b3b3b3 where the autocomplete component is using #757575. Maybe something like background-500 would be a better choice (400 seems too light, especially with hover)
This is now covered in Search Pattern of the Material spec.


As you can see from the updated spec, bold is used to indicate currently typed characters instead of decreasing the opacity of the text.
Opened https://github.com/angular/material/pull/11244 with the updates to the new spec guidance.
Looks right to me as Roboto Bold (700)