Regarding the gap problem… While you’re waiting to hear back, I would recommend opening a separate tab in your browser with a page/post that you’ve inserted an accordion on. Then go to the plugins section in the WP admin; then one-by-one, deactivate any plugins you have installed and reload the page/post in-between each deactivation to check for a change in the accordion’s appearance. Might even refresh twice just to be sure.
There’s one plugin I’ve come across that caused a somewhat similar distortion. Once activated, the accordion’s layout was immediately thrown off and the blocks became about 1.5 times their normal size. Long story short, your accordions should not look that way. They should appear just as they do in the preview. Though I would be interested to know how to make the edges of the blocks completely flush with one another. Anyway, it’s worth a shot. At the very least you’ll be able to rule-out a plugin conflict as the source of the problem.
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