Shortcode Updating Reports JSON error

Hi, there,

When editing the page on my test site, when I inserted the following shortcode:

[cpt_ajax_load_more post_type=”post” template=”default” posts_per_page=”8″]

and clicked “Update”, I got the following error message:

Updating failed. The response is not a valid JSON response.

However, the page DOES get updated, and seems to be working fine, so this is more an annoyance than a show-stopper.

I’m running WordPress 5.5.1. I tried disabling all other plug-ins, and also tried switching to another theme, but I always get this error whenever I update.

I used to use the “plain” Ajax Load More [ajax_load_more …] and I never got this error.

I’m running apache and PHP 7.4.10.

Any ideas?

Thanks.

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