We have identified an issue with signature management when composing emails with accounts that have multiple identities configured.

Symptoms:

• When composing a new email, the default user signature is inserted automatically
• When switching to a different identity, the new identity's signature is added to the message
• The original default signature is NOT removed, resulting in duplicate signatures
• Both the default user signature and the identity-specific signature appear in the email body

Expected behavior:
When switching to a different identity while composing an email, the previous signature should be removed and replaced with the signature associated with the newly selected identity. Only one signature should be present at any time.