A Blender 3.0 compatablity update of Blender2.8x-RenderButton v0.0.2 by Mitsuma, which I later realized was pointless when I noticed that the 0.0.3 version of that add-on was already compatable with Blender 3.0.
Download the latest ZIP from Releases.
Install via Edit > Preferences > Add-ons > Install…
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