Viewing and editing orphaned comments results in a fatal error

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I tried replicating on D10 and instead of a fatal error I get a 404. Could someone else confirm?

Moving to PNMI but if still an issue move to needs work as this will need test to show the issue.

Since there hasn't been a follow up going to close for now. If still a valid bug please reopen

Snapshot of latest state of MR for usage with composer patches on drupal/core:10.3.*

Will still need test coverage.

Issue summary should probably be updated too. "Add extra check" isn't a complete solution I'd say.

I verified the issue, unable to replicate. Below are the steps I followed to replicate the issue.

Scenario 1: Attached Entity removed
1. Added Comment to Article content type.
2. Created node, and added Comment to Node.
3. Added child comments to the parent comment.
4. Deleted Node programmatically using below script,

$nodeStorage = \Drupal::service('entity_type.manager')->getStorage('node');
$node = $nodeStorage->load(NID);
$node->delete();

5. Accessed the Comment Edit and Delete URLs.
6. Getting page not found page instead of Error.

Scenario 2: Attached Parent comment removed
1. Added Comment to Article content type.
2. Created node, and added Comment to Node.
3. Added child comments to the parent comment.
4. Deleted Parent Comment programmatically using the below script,

$commentStorage = \Drupal::service('entity_type.manager')->getStorage('comment');
$comment = $commentStorage->load(CID);
$comment->delete();

5. Accessed the Child Comment Edit and Delete URLs.
6. Getting page not found page instead of Error.