To ensure that the images used in the email editor are correctly displayed in mobile (are not getting zoomed/stretched), please follow the steps below:
- Double click on the media element (in which the image was configured) in the email template.
- Turn the "Auto-width" toggle off displayed under that Media element block settings.
- Check the box for "Full Width on Mobile"
Once finished the configuration should appear as seen below:
These settings will ensure that the images are being optimized in the Mobile view.