Image Transformation Format is Discarded on Frontend

[svedish]

Description

In CK Editor fields, Image Transformations formats, different from the uploaded files, seem to be ignored once the entry is saved (using Image Mode > Image tags).

Steps to reproduce

1. Create an Image Transformation with a specific format (e.g. WebP)
2. Upload a jpg image
3. Insert the Image in a CK Field (choose Transformation in the modal)
4. Inspect image in the Field / CP (it's the WebP file — correct)
5. Save
6. Inspect image again. It's the original jpg now.
7. Inspect front end. It's the jpg forced to the Image Transformation size with height and width

Additional info

• Craft version: 5.9.21
• PHP version: 8.3.14
• Database driver & version: MySQL 8.0.44
• CK Editor: 5.4.0

[linear-code]

PT-3128