Plugins causing Editor to Not Display Anything



I’m having a strange problem and could use some help. I made a few plugins, and I noticed they are ALL having this same problem. When i add them in the editor by placing the Plugin Element inside a group, It looks like everything is fine. But when I reload the page in the editor, the entire editor is blank. The content still appears in the navigator, but the page is blank:

Here you can see after I’ve added the plugin along with some text inside a group. I made the plugin. This is the code for the plugin Element preview, which i literally copied from the Javascript to Bubble plugin from Toolbox:

I don’t think the preview code has to do with the problem, as i have the same problem right now with ALL my plugins and some of them have no preview code. Anyways, If i reload the page, it works fine at this point. But if I change the Layout of the group in red from “Fixed” to “Column”, like so:

And then I reload the editor in the browser (Chrome), this is what I see:

You can see everything should be visible on the left, but nothing is displayed. When i view the console, I see this error message:

Any idea whats going on? A couple of things. If i change the Layout of the group back to fixed, and reload, its works again. Also, i’ve tried this with other plugins from the store, and they seem to work fine. It’s just my plugins (All 5 of them, still in testing mode) that don’t work. And also, there doesn’t seem to be any issues with how the page loads in preview. Everything renders fine, its just the editor it seems.

However, if i place a second copy of the same plugin on the page, but not inside a group (at the very top level), and with the layout of the red group still as Column, suddenly when I reload, it works again

If anyone has any explanation of what I’m doing wrong it would be hugely appreciated. Thank you.