WP Smush error in Custom Post Types (images not viewed in Gutenberg)

Hi,
I have a Custom Post Type in my theme. After struggling for days with an error, I have found that the plugin WP Smush is causing the issue.

When I insert a new image through WordPress editor (native Gutenberg), the page shows a message like “this block has encountered an error and cannot be viewed”. The image is shown in the front end, however, I am not able to edit the image in any way when the error appears.

Here is a screenshot of the error: https://tinyurl.com/qnt2uoo

Some information:
-> The error appears only in custom post types.
-> The error occurs in any way I choose to insert an image (upload, library or URL)
-> The Chrome Console shows a Javascript error: TypeError: Cannot read property 'strings' of undefined
-> When I disable WP Smush, the error is gone.

Does anyone could figure out a way to solve this error?
Thank you!