Recently I tried out the Azure Portal's Desktop App, available for download here:
Initially, I thought to myself that this would be a strange thing to use, as it seems to only load the web UI inside the app. However, after using it for a couple of days continuously, it has proven to be delivering a lot better response times for loading all the UI and blades than the Browser-based Portal.

You get pretty much the full experience, including the Azure Shell:

And my other favorite feature is the search, which is exceptionally responsive:

That's it, just a small tip - enjoy.
Edit: Side-note on how I found this:
Visiting the https://preview.portal.azure.com portal with IE gives you the option to download this app instead of using the somewhat limited/broken functionality of IE.

Resources
Additional links that can prove to be beneficial:
- Azure Portal Documentation (Microsoft Docs)
- What is the Azure Portal? (Microsoft Docs)
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