I've used this extension for years without issue, but I grabbed the Mac app today and hitting some weird behavior:
Error installing locally: error-downloading https://github.com/ryanpcmcquen/standardnotes_org_mode_editor/archive/gh-pages.zip
Here's the extension:
https://github.com/ryanpcmcquen/standardnotes_org_mode_editor
The link it is having trouble with downloads if I visit it directly. I am on version 3.4.4 of the desktop app.
If I try to enable the extension, things get really interesting:

And this call keeps failing in the network tab:
curl 'https://ryanpcmcquen.org/standardnotes_org_mode_editor/' -H 'authority: ryanpcmcquen.org' -H 'upgrade-insecure-requests: 1' -H 'user-agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_6) AppleWebKit/537.36 (KHTML, like Gecko) StandardNotes/3.4.4 Chrome/80.0.3987.165 Electron/8.2.5 Safari/537.36' -H 'sec-fetch-dest: iframe' -H 'accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9' -H 'sec-fetch-site: cross-site' -H 'sec-fetch-mode: navigate' -H 'accept-language: en-US' --compressed
Trying this link from the README worked fine for me. The extension hasn't had any performance issues in either the web app or desktop app.
Can you reproduce this behavior if you restart the app?
I can reproduce the flickering issue in v3.4.2 of the desktop app on Ubuntu, but not on Windows or the 3.5 beta for macOS.
I think it is a network issue ... maybe. I added a backup install link because gitcdn was being wonky today.
It could have been. I visited it directly and it triggered the download of the zip file within seconds.
@JaspalSuri, I am still having the issue and uninstalling and reinstalling.
It's worth noting that this extension works perfectly on iOS and the web.
@JaspalSuri, something is causing an infinite loop in the Mac OS desktop app:

What errors are outputted to the console tab? You may need to expand them, copy them, and then strip out any sensitive info before sharing them here.
No useful errors on the console, same issue on the Windows app. In the browser (Firefox), I get a prompt to allow the extension permission to access the note. I never get that prompt on the desktop app.
I was able to replicate this as well. Strange. Going to try to see if this is fixed with our 3.5 beta.
In other news, I switched the external links in my extension to jsDelivr, as gitcdn.link was occasionally giving 5XX errors. Not sure, but this could all be network related ...
The plot thickens, now when installing, two copies attempt to get installed:

Now, when trying to install the extension on web, I am getting a CORS blocker:
Content Security Policy: The page’s settings blocked the loading of a resource at eval (“script-src”). app.standardnotes.org:107:30
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://ghcdn.rawgit.org/ryanpcmcquen/standardnotes_org_mode_editor/gh-pages/org_mode.json. (Reason: CORS header ‘Access-Control-Allow-Origin’ missing).
@mobitar, any ideas on the CORS issue in Firefox?
I'm not sure rawgit was ever acceptable, as they are missing the correct headers for CORS. Did it work before? I'd say try your own CDN or one that returns proper headers (you can try S3).
It has always worked until now, and it does install inside the app, just not in the browser on Firefox.
I was able to reproduce the duplicate extension issue in the internal desktop beta. I'll make an additional report for this.
Edit: sorry, I didn't see the replies above; they didn't kick in until after I had sent my message.
I believe I at least resolved the installation issue in Firefox by switching to gitcdn.xyz, it seems to be working well again, hopefully it stays reliable ...
Thank you for providing all of this information by the way! We've logged your issue in our private tracker and I intend to take a deeper look at it 👍
Hey again! I noticed that the extension repo has no package.json file. Theoretically you don't need it, but the app is at least expecting it to be there at the moment. We're going to fix this on our end but in the meantime you can create a package.json file in the repository and it should fix the looping issue 🙂
Most helpful comment
Hey again! I noticed that the extension repo has no
package.jsonfile. Theoretically you don't need it, but the app is at least expecting it to be there at the moment. We're going to fix this on our end but in the meantime you can create apackage.jsonfile in the repository and it should fix the looping issue 🙂