Docs and info link

docs/usage.md

@@ -251,6 +251,10 @@ different means. These are as follows:
 Paperless is set up to check your mails every 10 minutes. This can be
 configured via [`PAPERLESS_EMAIL_TASK_CRON`](configuration.md#PAPERLESS_EMAIL_TASK_CRON)
 
+#### Processed Mail
+
+Paperless keeps track of mails it has processed in order to avoid processing the same mail multiple times. This uses the message `UID` provided by the mail server, which should be unique for each message. You can view and manage processed mails from the web UI under Settings > Mail > Processed Mails. If you need to re-process a message, you can delete the corresponding processed mail entry, which will allow Paperless to process the mail again the next time the mail fetch task runs.
+
 #### OAuth Email Setup
 
 Paperless-ngx supports OAuth2 authentication for Gmail and Outlook email accounts. To set up an email account with OAuth2, you will need to create a 'developer' app with the respective provider and obtain the client ID and client secret and set the appropriate [configuration variables](configuration.md#email_oauth). You will also need to set either [`PAPERLESS_OAUTH_CALLBACK_BASE_URL`](configuration.md#PAPERLESS_OAUTH_CALLBACK_BASE_URL) or [`PAPERLESS_URL`](configuration.md#PAPERLESS_URL) to the correct value for the OAuth2 flow to work correctly.

src-ui/src/app/components/manage/mail/processed-mails-dialog/processed-mails-dialog.component.html

@@ -1,5 +1,12 @@
 <div class="modal-header">
   <h6 class="modal-title" id="modal-basic-title" i18n>Processed Mails for <em>{{ rule.name }}</em></h6>
+  <button class="btn btn-sm btn-link text-muted me-auto p-0 p-md-2" title="What's this?" i18n-title type="button" [ngbPopover]="infoPopover" [autoClose]="true">
+    <i-bs name="question-circle"></i-bs>
+  </button>
+  <ng-template #infoPopover>
+    <a href="https://docs.paperless-ngx.com/usage#processed-mail" target="_blank" referrerpolicy="noopener noreferrer" i18n>Read more</a>
+    <i-bs class="ms-1" width=".8em" height=".8em" name="box-arrow-up-right"></i-bs>
+  </ng-template>
   <button type="button" class="btn-close" aria-label="Close" (click)="close()"></button>
 </div>
 <div class="modal-body">

src-ui/src/app/components/manage/mail/processed-mails-dialog/processed-mails-dialog.component.ts

@@ -4,6 +4,7 @@ import { FormsModule, ReactiveFormsModule } from '@angular/forms'
 import {
   NgbActiveModal,
   NgbPagination,
+  NgbPopoverModule,
   NgbTooltipModule,
 } from '@ng-bootstrap/ng-bootstrap'
 import { NgxBootstrapIconsModule } from 'ngx-bootstrap-icons'
@@ -20,6 +21,7 @@ import { ToastService } from 'src/app/services/toast.service'
     ConfirmButtonComponent,
     CustomDatePipe,
     NgbPagination,
+    NgbPopoverModule,
     NgbTooltipModule,
     NgxBootstrapIconsModule,
     FormsModule,