Problem after update to version 1.2.4

After updating to the last version (1.2.4) of wp pagebuilder on a test site, the formatting in textblocks gets lost after saving the page. It is visible while editing.

Furthermore I saw on a another test site that I can’t edit an existing page in the plugin allthough in that site textblocks show with formatting intact.

I can’t figure out so far why these 2 testsites behave different.

Both test sites are on wp 5.7 and all other plugins are up-to-date. On both I use the Gantry framework and until version 1.2.3 of the wp pagebuilder plugin that was no problem.