Jetpack: MailChimp Block Success Message has White Text

[jorgefilipecosta]

report by @marcuswisecaesar at https://github.com/WordPress/gutenberg/issues/18647.
Describe the bug
First noticed in 2482935-zen on a Simple Site when adding a Jetpack Mailchimp block, the success message after submitting an email address comes through as white text on the white background of the site.

To reproduce
Steps to reproduce the behavior:

1. On a core WordPress.com site add the MailChimp Block to a Page.
2. Publish the Page.
3. View the Page and enter a test e-mail address into the Form.
4. You will see Processing, but then nothing...

Expected behavior
Expected to see Processing message, and then Success as set in the Block Editor.

Screenshots

Direct Link

Desktop (please complete the following information):

• OS: OS X Catalina
• Browser: Chrome
• Version: 78

[jeherve]

It seems the problem is limited to WordPress.com simple sites; there the CSS variable --color-success is not transformed in #008a00. In Jetpack it works.

cc @sirreal who brought in those changes in #13503.

[sirreal]

It seems the problem is limited to WordPress.com simple sites; there the CSS variable --color-success is not transformed in #008a00. In Jetpack it works.

cc @sirreal who brought in those changes in #13503.

👋 @simison

[ockham]

From a quick glance, this seems like it could be due to the same issue as I described here: https://github.com/Automattic/jetpack/pull/13854#issuecomment-550898168

[simison]

FYI @jeffersonrabb who's working on MailChimp block iteration. Wanna help fix this small bug? :-)

[simison]

Found the problem, fix at D35821-code

[simison]

Fixed in r199801-wpcom