# \[Bug\]: Windows preview snapshots and remote viewing stall while T3 is completely covered · Issue \#23139 · pingdotgg/t3code

[View on GitCafe](https://git.cafe/pingdotgg/t3code/issues/23139)

Repository: [pingdotgg/t3code](https://git.cafe/pingdotgg/t3code)

Visibility: public

State: backlog

Priority: 0

## Description

[Discussion and activity](https://git.cafe/pingdotgg/t3code/issues/23139)

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## Environment

- T3 Code: 0.1.2-nightly.20261021.3486
- Host: Windows 11 x64
- Remote viewer: Android app 2.0.0, build 350

## Reproduction

1. Maximize T3 Code.
2. Maximize another application, such as Chrome, over it so T3 is completely covered.
3. Have an agent open https://example.com using preview_open.
4. Request preview_snapshot.
5. Bring T3 back to the foreground and repeat the snapshot.

## Actual behavior

While T3 is completely covered:

- preview_open and preview_evaluate return promptly.
- preview_snapshot consistently fails after approximately 10 seconds, reporting:
  "Preview automation snapshot timed out after 15000ms"
- This happens both with and without includeImage.
- One attempt also reported:
  "No preview automation host is available"
- The Android viewer remains on "Connecting to browser".

Once T3 is brought to the foreground, the same tab's snapshot succeeds immediately and Android can view it.

## Expected behavior

Agent snapshots and remote viewing should continue working when another application completely covers the Windows T3 window.

## Checks already performed

The failure reproduced with:

- Both Claude and Codex agents.
- Default and Incognito browser profiles.
- One tab and multiple tabs.
- A Home Assistant login page and example.com.

This reproduction concerns a fully covered window, not necessarily a minimized window.

## Related work

- #22743: proposed desktop background-tab hosting fix.
- #21494: proposed fix for text-only snapshots unnecessarily waiting for screenshots.
- #16567: earlier background-snapshot report. Its closing maintainer comment acknowledged remaining background-capture failures and requested a focused new issue.

This adds a repeatable Windows covered/uncovered comparison. It does not establish that Chromium window occlusion is the sole cause, and none of the proposed fixes has been tested locally.