As you can see, the reply button has been clicked. It's grayed out. But the page stays stuck there. And when I refresh, my attempted comment is nowhere to be found.
The Firefox error codes are also different between having this extension enabled and not having it enabled. I'll post those in the comments.
TypeError: a.default.detectStore(...) is undefined h1-check.js:1:1301
u moz-extension://2f8d5173-b65b-4298-80db-d9b001c62530/h1-check.js:1
1337 moz-extension://2f8d5173-b65b-4298-80db-d9b001c62530/h1-check.js:1
n moz-extension://2f8d5173-b65b-4298-80db-d9b001c62530/h1-check.js:1
<anonymous> moz-extension://2f8d5173-b65b-4298-80db-d9b001c62530/h1-check.js:1
<anonymous> moz-extension://2f8d5173-b65b-4298-80db-d9b001c62530/h1-check.js:1
inject resource://gre/modules/ExtensionContent.sys.mjs:581
InterpretGeneratorResume self-hosted:1455
AsyncFunctionNext self-hosted:852
with Bionic Reader enabled
Click here
TypeError: a.default.detectStore(...) is undefined h1-check.js:1:1301
Content-Security-Policy: The page’s settings blocked the loading of a resource at https://fonts.googleapis.com/css2?family=Roboto:wght@400;500;700&display=swap (“style-src”). utls.js:150:15
Content-Security-Policy: The page’s settings blocked the loading of a resource at https://fonts.googleapis.com/css2?family=Roboto+Serif:opsz,wght@8..144,400;8..144,500;8..144,600;8..144,700&display=swap (“style-src”). utls.js:150:15
Content-Security-Policy: The page’s settings blocked the loading of a resource at https://fonts.googleapis.com/css2?family=Roboto+Mono:wght@400;500;600;700&display=swap (“style-src”). utls.js:150:15
Uncaught DOMException: Node.insertBefore: Child to insert before is not a child of this node
b https://reddthat.com/static/7197474/js/client.js:2
He https://reddthat.com/static/7197474/js/client.js:2
Fe https://reddthat.com/static/7197474/js/client.js:2
Fe https://reddthat.com/static/7197474/js/client.js:2
Fe https://reddthat.com/static/7197474/js/client.js:2
Fe https://reddthat.com/static/7197474/js/client.js:2
Fe https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
e https://reddthat.com/static/7197474/js/client.js:2
$e https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
e https://reddthat.com/static/7197474/js/client.js:2
$e https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
e https://reddthat.com/static/7197474/js/client.js:2
$e https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
Je https://reddthat.com/static/7197474/js/client.js:2
e https://reddthat.com/static/7197474/js/client.js:2
$e https://reddthat.com/static/7197474/js/client.js:2
Ye https://reddthat.com/static/7197474/js/client.js:2
lt https://reddthat.com/static/7197474/js/client.js:2
it https://reddthat.com/static/7197474/js/client.js:2
setState https://reddthat.com/static/7197474/js/client.js:2
handleSubmit https://reddthat.com/static/7197474/js/client.js:2
n https://reddthat.com/static/7197474/js/client.js:2
c https://reddthat.com/cdn-cgi/scripts/7d0fa10a/cloudflare-static/rocket-loader.min.js:1
client.js:2