Header Text color option doing two jobs, so both suffer

[joyously]

There are two issues, both of which have been addressed before. #23761, #22498

The Header Text color option and the Display Site Title and Tagline option use the same storage space (theme_mod), so there is no way to hide the title and use the color for other header text, and when the title is unhidden the color is (sort of) the default.

Steps to reproduce:

1. In Customizer, note the header text color for comparison later.
2. Hide the site title.
3. Save and exit the Customizer.
4. Open Customizer and unhide the site title.
5. Look at the header text color and compare to value from step 1.

What I expect:

1. The header text color could be used for other header text besides the site title. Hiding the title should not hide the color selection.
2. The color set before the title was hidden should be restored when the title is unhidden.

What actually happens:

1. The color option is used to indicate the visibility of the site title, so the color is set to 'blank'.
2. Other text in the header cannot be styled with the header text color if the site title is hidden.
3. When the site title is unhidden, the header text color option shows a color for the swatch that is the default color, but the text input box is empty and the color indicator shows black (as if it were 0).

Or just set the color of the header text, hide it, unhide it, and the color you chose is gone.

I think it should be two separate options for color and hiding. I don't know how that would affect backward compatibility, but it is the best solution.

[joyously]

Note the white swatch (and text), the empty input box, and the black color indicator.

[joyously]

Ignore this line:

Or just set the color of the header text, hide it, unhide it, and the color you chose is gone.

[mukesh27]

@joyously, Yes it's bug. it will persist when we close Customizer panel otherwise color field value not removed. check attached video for more information.

[callumbw95]

Hi All,
I have taken a look at this, and it appears to be specific to the 2017 theme. I can confirm the issue still exists, however as it is an 8 year old theme, this most likely won't get any changes / fixes merged in.
Also with WordPress's focus on the block-based Site Editor for theme and site management, new features and significant UI changes for the Customizer (or classic Widgets screen) are no longer being implemented in Core. The functionality described here has been superseded by modern workflows in Full Site Editing. As of such I will mark this ticket as closed, but a shame this ticket didn't get any traction back when it was more relevant...

[joyously]

Just to be clear, this issue is not specific to the 2017 theme. That theme was used as an example. I had the same problems with my own theme, because the options involved are core options stored in theme_mod by code that is in core.
I just tested WP 6.8.1 and the Customizer is still available, and used by thousands of themes that came before the site editor. Even with the 2021 theme, the option to hide the Site Title and Tagline is there (core option), but that theme doesn't use the core option for Header Text color.
So I think you(@callumbw95) didn't look at the real issue closely enough to see the truth. The code is still part of the WP product and it is still broken.

Aside: I used wpsandbox to quickly test this, and although I don't know what they do to configure a blank test site(strangely the Dashboard had no widgets), they have it set to start with the 2020 theme, which uses Customizer but not these particular options. Maybe your "modern" workflow is not embraced by everyone.