Version 1.1.0 implements mobile support; version 1.1.1 fixes timeout and overlapping-insertion recovery, and version 1.1.2 handles an absent logo marker and adds safe failure references. Both patches use the same manifest. Automated checks and XML validation pass; real-phone acceptance is pending. The reported test client is Outlook for Android 5.2630.0 (72630118).

Version 1.2.0 adds a desktop shared-mailbox setting in manifest 1.2.0.0, retaining the same mobile declaration. Outlook does not support add-ins in mobile shared mailboxes. This phone test applies to a user's own Microsoft 365 mailbox.

New messages get the existing full signature with embedded outlined logos. Replies and forwards get the existing compact signature. From changes rerun insertion using the same verified-alias checks. Outlook SSO still reads only the signed-in user's profile with delegated User.Read.

The mobile path uses HTML directly because body.getTypeAsync is unsupported. It also avoids getAttachmentsAsync, which is not among the supported later mobile APIs. Successful logo attachments are recorded in per-item session data so another compose/From event can reuse them. Markers contain only asset filenames and an added flag; they contain no employee information or access tokens.

A new draft has no marker yet. Version 1.1.2 treats KeyNotFound (9050) from the marker read as this expected initial state. Other failures still stop insertion. If a refresh fails, the banner can include a safe reference such as session-read/OUTLOOK_9051 or signature-write/OUTLOOK_5001; share that exact reference with IT. Opening the received-message pane diagnoses its own connection and preview, not a previous compose event.

Mobile insertions for the same item are queued within one runtime. Successful uploads are recorded even if the local deadline expired while the upload was pending; cancellation still prevents the next upload and signature write. Host termination or a failed marker write can still leave an unrecorded attachment. See the review assessment.

1. Merge the reviewed change and wait for successful Pages publication. Verify the hosted code and https://arklab.github.io/manifest.xml are from the same build.
2. In Microsoft 365 Settings → Integrated apps → ARK signatures, update the existing app's manifest to the published 1.2.0.0 file. Mobile was introduced in 1.1.0.0; the current update adds desktop shared-mailbox activation. Retain the existing app ID and assigned users. Do not create a duplicate production add-in or change Graph permissions.
3. Verify the saved update and allow Microsoft to deliver it. Publishing GitHub Pages does not update the manifest stored by Microsoft 365. A manifest update can incur Microsoft's deployment propagation delay.
4. Restart Outlook on the test phone after delivery, then run the checks below. Updating the shared manifest enables mobile for all existing assigned users, not just the tester. Do not remove desktop users to narrow this test.

The old desktop installation continues to use the desktop path while manifest delivery is pending. The mobile declaration also covers iOS; it does not establish that iOS has passed acceptance.

The 1.1.1 and 1.1.2 patches change hosted code only; an existing 1.1.0.0 Microsoft 365 manifest does not need another update. Restart Outlook if it retains the previous runtime.

Use Outlook 4.2502.0 or later, a Microsoft 365 business mailbox and a working connection. This minimum covers SSO, per-item session data and both supported compose/From events used by this app. No additional Microsoft permission or Entra app registration is required.

1. Open a received email and locate ARK signatures in the message's add-ins/menu. This opens a preview of your own profile. If Microsoft requests a sign-in check, choose Continue with Microsoft 365. The add-in does not modify the received email.
2. Close the panel and create a fresh email. Wait for the signature, send a test and inspect both the received email and Sent Items. Confirm names, job title, numbers, logo appearance and links.
3. Start a reply and a forward. Confirm the compact signature is beneath the new text. Expand a quick reply to full screen to see the signature.
4. If another assigned personal Exchange account is available in the From dropdown, switch to it and verify that account's signature. Microsoft does not support SMTP alias or shared/delegated mailbox From-change scenarios on mobile; test aliases on desktop.
5. Repeat after leaving Outlook idle, and after restarting it. Test light and dark mode and a narrow portrait display.
6. Check a temporary network failure. The add-in should preserve the current signature and complete its event without sending mail or overwriting the body. After reconnecting, start a new draft.

Keep employee screenshots and mail samples in internal records, outside this public repository.

• Shared-mailbox add-ins and shared/delegated mailbox From-change events are not supported on Android or iOS. A desktop manifest change cannot enable them on mobile. Microsoft's shared-mailbox support matrix and From-change event limitations.
• The add-in runs automatically in compose; the manual pane is available when reading a message. There is no mobile Refresh this message button. After resolving a connection failure, create a new draft; reopening a saved draft does not fire the new-message event.
• A mobile event has a 60-second maximum and ends when the user sends or closes the message. Sending immediately can interrupt insertion; this app does not block sending or enforce signatures.
• Quick-reply signatures may be hidden until the composer is expanded.
• Offline profile retrieval cannot succeed. No employee directory cache or server-side signature service is introduced.
• The mobile API cannot enumerate attachments. Session markers prevent this add-in from repeatedly adding its own logo in the same session; they cannot detect a logo the user manually deletes. In that case, start a fresh draft.
• Outlook on iOS is enabled by the same manifest declaration but remains unverified. Apple Mail and other Android mail apps do not run this add-in.

• Mobile event-based signatures and limitations
• Supported and unsupported mobile APIs — supported API exceptions can run even when the manifest requirement is higher than Mailbox 1.5; this manifest retains the desktop requirement of 1.13.
• NAA client requirements — mobile SSO from 4.2433.0.
• Mobile add-in commands
• Per-item session data