UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36

Steps to reproduce the problem:
Scenario 1:

1. Right-click on Windows 10 desktop > Personalise > Colours. Ensure that "Title bars" underneath "Show the accent colour" is NOT checked.

2. Observe that by default, Chrome uses a medium-grey colour for the frame (ie. title bar) and inactive tabs when no theme has been applied. See screenshot-1 of the active & inactive tabs and frame colour.

3. Create a Chrome theme per https://developer.chrome.com/extensions/themes

4. In the theme's manifest.json file, do *not* include the "frame" colour value (nor any image for the frame). Therefore the theme does not specify any colour for the frame.

5. Apply the theme.

6. Observe that the Chrome frame continues to use the same default grey colour that is used when no theme has been applied. In other words, not specifying a frame colour in the theme means Chrome uses the default colour for the frame/title bar. This is expected behaviour.

Scenario 2:

1. Remove theme. Right-click on Windows 10 desktop > Personalise > Colours. Set a colour, eg. blue. Ensure that "Title bars" IS now checked.

2. (With no theme applied) observe that Chrome now uses the Windows colour (blue) for its frame and inactive tabs. This is still expected behaviour. See screenshot-2.

3. Create a Chrome theme per https://developer.chrome.com/extensions/themes

4. In the theme's manifest.json file, do *not* include the "frame" colour value (nor any image for the frame). Therefore the theme does not specify any colour for the frame.

5. Apply the theme.

6. Observe that the Chrome frame reverts back to the default grey colour that is used when "Title bars" is not enabled. In other words, Chrome does not inherit the Windows colour specified in the Settings panel, even when no frame colour is defined in the theme. See screenshot-3.

What is the expected behavior?

What went wrong?
Expected behaviour:

If a frame colour is not defined in the theme, and if "Title bars" is enabled in the Windows Settings panel, then Chrome ought to use the Windows colour from the Settings panel for the frame/title bar.

That way, theme designers can allow the user the flexibility to chose their own frame colour via the Windows Settings if they wish to. Alternatively, if the theme designer does not wish the user to chose their own frame colour, then the theme designer can easily override this by specifying a frame colour in the theme, which would take priority.

In short: if Chrome allows the user to specify the frame colour (via Settings panel) when no theme is applied, then it ought to also be possible to do this when a theme *is* applied, as long as the theme itself is not specifying any frame colour.

Did this work before? N/A 

Chrome version: 71.0.3578.98  Channel: stable
OS Version: 10.0
Flash Version:
 

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