(TEST FORUM) Malformed mailto: link when trying to share a post

Steps to reproduce

  1. Open a thread.
  2. Click share.
  3. Click the envelope icon

Expected results
Your default mail client opens with the thread title in the subject.

Actual results
Your default mail client opens with “&subject=” in the sender field.

Reason
The mailto link is currently:

mailto:?to=&subject=%5BDiS%20Self%20Hosted%20Test%5D%20Selfie%20Test%20%3Acold_face%3A&body=https%3A%2F%2Fdiscourse.drownedinsound.co.uk%2Ft%2Fselfie-test%2F159%3Fu%3Dma0sm'.

It should be

mailto:?subject=%5BDiS%20Self%20Hosted%20Test%5D%20Selfie%20Test%20%3Acold_face%3A&body=https%3A%2F%2Fdiscourse.drownedinsound.co.uk%2Ft%2Fselfie-test%2F159%3Fu%3Dma0sm'.

There’s an additional to=& which breaks the link there.