Automatically place system block in regions on theme install

[AlexVanK]

It's possible to automatically configure and place certain system block in the regions provided by the theme, upon theme installation.

Automatically configure the following:

• Branding (Logo)
• Breadcrumbs
• Page Title
• Content
• Messages (Bootstrap system alerts)
• Search Form
• Tools (this is the utility nav that goes under the search bar)
• Local Tasks (these are the tabs that appear above a page's content when logged in)

There could be other blocks to configure automatically, but they very much depend on the layout the site will have and the available regions.

Custom blocks are not configurable as of now: @see: https://www.drupal.org/forum/support/theme-development/2020-01-25/possible-to-create-a-custom-block-with-content-at-theme

‼️ - Important - This applies to the subtheme branch as well

[AlexVanK]

Done. Added to subtheme repo as well,