I'm filing this as a candidate sub-issue of the #151 META...
There's the Views Watchdog module for Drupal that does this (could be others too) and we can use that as a starting point. I imagine that the "Top 'access denied' errors" (/admin/reports/access-denied) and the "Top 'page not found' errors" (/admin/reports/page-not-found) report pages can then simply be filtered versions of the same view and on top of that we can expose whichever of these views/displays as blocks that can be then used in #495 to create a (highly customizable may I add) dashboard.
Thoughts?
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Worth mentioning as it was in zulip chat by @yorkshirepudding I just tested and the two work together without issue as long as you don't use the "Exclude comments from Content...
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There is also Node Comments Search - this searches the node and all comments (default search is node and first page of comments) as part of the content search. Izzy's module above is a separate...
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I have created a new module comment_search
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