# Pull Request Template
## Description
This PR includes,
On Windows, pressing **Ctrl+Enter** in the reply editor was inserting an
unintended line break before sending. This led to two issues:
* **Unexpected blank lines**
After adding a line break with Shift+Enter and removing it with
Backspace, the editor looked correct. However, sending with Ctrl+Enter
reintroduced a hidden break, resulting in an extra blank line in the
final message.
* **Selected text being replaced**
When text was selected and Ctrl+Enter was pressed, the selection was
replaced with a line break instead of being sent.
Fixes
https://linear.app/chatwoot/issue/CW-6840/newline-bug-in-the-editor
### **Cause**
Two keyboard handlers responded to **Ctrl+Enter** on Windows:
* ProseMirror (`Mod-Enter`) inserted a hard break
* ReplyBox (`$mod+Enter`) triggered send
The existing guard only checked `metaKey` (Cmd), so it never worked on
Windows. As a result, a line break was inserted just before sending.
### **Solution**
Make the modifier check platform-aware so the editor correctly
intercepts the send shortcut:
* Added `detectOS`, `isMac`, and `OS` constants
* Introduced `hasPressedMod` (uses `metaKey` on macOS, `ctrlKey`
elsewhere)
This ensures Ctrl+Enter sends the message without modifying content,
while keeping existing behavior unchanged.
**NB:** macOS behavior with Cmd+Enter remains unchanged
## Type of change
- [x] Bug fix (non-breaking change which fixes an issue)
## How Has This Been Tested?
**Case 1: line break**
1. Type `hello`
2. Press Shift+Enter, then Backspace
3. Press Ctrl+Enter
→ Message contains an unexpected blank new line
**Case 2: Selection replaced**
1. Type two lines using Shift+Enter
2. Select text on the second line
3. Press Ctrl+Enter
→ Selected text is replaced and not sent
### Screencast
**Before**
https://github.com/user-attachments/assets/d6d285a9-260b-4711-8bbd-d0c8519e8d20
**After**
https://github.com/user-attachments/assets/c0ace1f7-5d22-44a2-8e08-22190ee21e61
## Checklist:
- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [x] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules
