+
+## How do I search for the `List-Id:` header?
+
+Currently there is no way to search for `List-Id:`. As a workaround, try using a
+`to:` prefix search (which covers both `To:` and `Cc:` headers) on the mailing
+list address.
+
+Limitations in the duplicate message handling are the main reason for not
+indexing the `List-Id:` header. If you receive the same message via both the
+list and directly (by way of `To:` or `Cc:`), only the first message encountered
+will be indexed. Only the message received via the list will have `List-Id:`,
+but you would expect a `List-Id:` search to find the message, regardless of the
+order in which the duplicates were received. This is a more general problem than
+just `List-Id:`, and once this has been resolved, adding `List-Id:` indexing is
+trivial.
+
+## Can I use notmuch with grsec?
+
+Sure! It works out of the box. If you have TPE enabled (trusted path execution),
+make sure the user is executing the script belongs to the
+`kernel.grsecurity.tpe_gid` (in debian this is grsec-tpe).
+This is required in order to run the `pre-new` and `post-new` hooks.