Q: Email signature

Hello ashelal,

I'd be happy to assist with your Mail signature issue. I recommend that you try creating a new signature with a different image to see if the problem persists. If the problem doesn't persist with a new test image, the original image you selected may need to be edited to work correctly with your signature.

If you notice the same behavior after trying with a different image, I would then recommend creating a new test user account on your Mac to see if the unexpected behavior occurs there as well. This link provides great instructions to complete this task: How to test an issue in another user account on your Mac - Apple Support

Create a test user account

1. From the Apple menu, choose System Preferences.
2. Click the Users & Groups icon in the System Preferences window.
3. Click the lock icon, then enter an administrator name and password.
4. Click the Add button (+) below the list of users.
5. Choose a type of user from the New Account pop-up menu.
6. Give the user a full name, account name, and password.
7. Click OK.
8. Close the System Preferences window.

 Once you have created the test user account, log out of your current user account and try reproducing the issue by creating a new signature.

Cheers.