[BUG] Claude Desktop: Send button silently fails - message disappears when context is high

[ThatDragonOverThere]

Description

When context usage is high (near compacting threshold), clicking the send button appears to work momentarily but then silently fails - the UI reverts to the state before sending, as if the message was never submitted. No error message is displayed.

Steps to Reproduce

1. Use Claude Desktop until context usage is high (near auto-compact threshold)
2. Type a message and click send (arrow button)
3. Observe: UI "resolves" for a second, then reverts to pre-send state
4. Message is gone, no error shown

Expected Behavior

Either:

• The message should send successfully, OR
• An error message should appear (e.g., "Context limit reached - /compact or /clear to continue")

Actual Behavior

• Send button click appears to work briefly
• UI then silently reverts to state before sending
• No message appears in conversation
• No error message displayed
• User left wondering what happened

Environment

• Platform: Windows
• Application: Claude Desktop (GUI app)

Notes

This may be related to context/compacting issues but the silent failure with no error is the core UX problem. Users should never have a message silently disappear without feedback.

Possibly Related Issues

• #17292 - Autocompact not triggering at high context usage
• #16937 - Chat rollbacks/disappearing responses (closed as dup of #10065)
• #18178 - Context percentage mismatch