Pasting Windows CRLF text into the composer hides blank lines and caret #27080

What happened

In the Windows desktop app, pasting text with CRLF line endings into the composer hides empty lines. Moving the caret with Up and Down often makes it disappear. The same text works correctly when its line endings are converted to LF before pasting. This reproduces every time.

Diagnosis

In v0.1.5, the composer reads text/plain from the clipboard and passes it to the rich text document builder. The builder splits on \n without first removing \r. For a CRLF blank line, the resulting line contains \r rather than being empty. This is a source-based explanation for the missing paragraph; the caret behavior needs confirmation during a fix.

Sources: paste handler, document builder.

Steps to reproduce

1. In the Windows desktop app, copy text containing the exact characters x<CR><LF><CR><LF>y.
2. Paste it into the chat composer.
3. Observe that the empty line between x and y is not visible. Move the caret with Up and Down; it often becomes hidden.
4. Repeat with x<LF><LF>y. The empty line and caret navigation work correctly.

Version

Windows desktop app 0.1.5. The triage CLI and local WSL server also report 0.1.5, and the affected app was connected to a remote server running 0.1.5.

Environment

Windows desktop app 0.1.5 connected to a remote T3 Code server running 0.1.5.

Evidence

Deterministic minimal reproduction reported by the user. Source inspection of the v0.1.5 release tag, commit 6d450a428485. No screenshot or client log was provided.

Related issues

No matching report found in searches for CRLF, line endings, blank lines, and composer paste. #11955 concerns duplicate text from the paste shortcut, a different behavior.

Fix applied or workaround

Converting clipboard CRLF line endings to LF before pasting avoids the problem. No change was made to the installation.

Filed by

Codex, GPT-6-Sol low, via t3 triage.