The following theme is missing from the file system: jquery_ui_resizable

Downgrading the module to 3.31 causes the error to disappear. This seems to indicate it is an issue with 3427365 somehow.

This error appears simultaneously when the theme upgrades past 3.31:

Deprecated function: dirname(): Passing null to parameter #1 ($path) of type string is deprecated in Drupal\Core\Extension\ExtensionPathResolver->getPath() (line 85 of core/lib/Drupal/Core/Extension/ExtensionPathResolver.php).

...specifically, in relation to LibraryDiscoveryParser->buildByExtension() which would indicate an issue with including the library. We definitely have the https://www.drupal.org/project/jquery_ui_resizable → installed and enabled. If some other step is required, I haven't seen that indicated anywhere in any documentation.

Have you tried the latest releases 3.35 or 3.36?

╭─◀ ☕ joseph.olstad laptop ▶ ~/drupal.org/bootstrap ▶ 📂9 📃23 🔗0 ▶ 🔀 8.x-3.x ▶
╰❯ $ grep jquery_ui_resi * -iR

bootstrap.info.yml:  - jquery_ui_resizable:jquery_ui_resizable
bootstrap.libraries.yml:    - jquery_ui_resizable/resizable
composer.json:    "drupal/jquery_ui_resizable": "^2.1.0",

Please also review the release notes:

Important Notes

There are new dependencies. However, since this is a theme, it cannot enable those modules through an update hook. After updating, enable/install these modules:

• jquery_ui
• jquery_ui_draggable
• jquery_ui_resizable

Creditting