bug(material/table): Row of sticky column is transparent on hover in custom dark theme

[calebkish]

Is this a regression?

• Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

14.2.7

Description

https://stackblitz.com/edit/angular-nhbxgc?file=src/app/table-sticky-columns-example.html

Reproduction

Steps to reproduce:

1. Custom material dark theme is applied
2. In table that has a sticky column, try horizontal scrolling.
3. The hover row in the sticky column is transparent so other columns show beneath it.

Expected Behavior

I expect the hovered row of the sticky column to not be transparent in a custom dark theme.

Actual Behavior

The hovered row of the sticky column is transparent in a custom dark theme.

Environment

• Angular: 15.2.1
• CDK/Material: 15.2.1
• Browser(s): Chrome, Firefox
• Operating System (e.g. Windows, macOS, Ubuntu): Windows

[calebkish]

note that there's another bug which appears in that GIF, where the hover styling for table rows isn't getting applied when using a custom material light theme. Related issue: #26203

[jgoldb]

This is still an issue in v16.1.7 and can also effect sticky footer rows. It can also be reproduced on the material docs site (material.angular.io) by switching back and forth between Deep Purple & Amber and any other theme a couple times. This causes table row backgrounds to become slightly transparent on mouseover.