Cannot run update.php

Not clear to me what the issue is either, but the suggested fix of removing the offending twig files fixed it for me as well.

Here's a related core issue, though not clear that it's actually a core problem or how to recreate with only core: 🐛 array_diff(): Argument #2 must be of type array, null given in array_diff() (line 702 [...] core/lib/Drupal/Core/Theme/Registry.php) Postponed: needs info

I will open a MR with the suggested fix as a temporary workaround.

In my case, removing this file bootstrap/templates/block/block.html.twig
resolved the update.php issue.

In the end, it boils down to my custom theme hook implementation.
customTheme_preprocess_block__BlockID()
I removed that and update.php works.

Marking as fixed as this was released in the 8.x-3.32 → and fixed the issue for me - tested on the latest Drupal core 10.3.2.

Remove file generate error : Twig\Error\LoaderError: Template "themes/contrib/bootstrap/templates/block/block--system-menu-block--main.html.twig" is not defined.

I also experienced this issue and noticed the problem was the same as in comment #8: by commenting out the theme__preprocess_block__simple_block(&$variables) in the custom theme, rebuilding registry and I was able to run the update without problems. I don't think deleting templates is the correct way to fix this. I would recommend looking into your .theme file.

Encountered this issue after upgrading a site from 10.2.x to 10.3.x which included bumping this theme to 3.32.

Even down to trying out the previous advice 'In my case, removing this file bootstrap/templates/block/block.html.twig
resolved the update.php issue.' which worked, but I wasn't too keen on that as a permanent fix.

I'm entirely sure that all composer commands were run successfully when the issue occurred, but I simply re-ran `composer require 'drupal/bootstrap:^3.32', composer re-evaluated and regenerated a number of autoload files and following that database updates ran successfully. The issue seems to be resolved for the site that was affected.

This might sound like I missed something, and maybe I did, but I haven't been able to track down what. May just be worth a try as a first pass if anyone else runs into this issue.