Emails created by the sendimages plugins don't contain any attached pictures, when using "adjust picture parameters". 
The resized pictures are presents in the user's home folder. 

Reproducible: Always

Steps to Reproduce:
1. select pistures to send by mail
2. choose export>send by email
3. select "adjust picture parameters", choose the parameters you want, then click "send"
4. a new email compositing window appears, but with no attachement
5. the resized pictures are located in home folder, and are note deleted when closing the sendimage dialog windows ("Terminate")

Actual Results:  
Resized pictures are not attached to the new email (non-resized pictures are correctly attached).
The resized pictures are present in the user home folder.

Expected Results:  
Resized pictures are attached to the created email.
Resized pictures are not presents is the user's home folder. 

KF5 5.24.0
Qt 5.7.0
Digikam & kipi-plugins 5.0.0