My co-worker ran into this error where new "Scene Variable" instances were being non-stop generated. I've seen this once before about 2 months ago, where the solution was simply to update to the latest version of Bolt.
Unfortunately, we're at the latest version, and curiously he's at a slightly newer version than me for "Bolt State" and "Bolt Flow". He's at 1.2.2 for both of those (1.2.0 for "Bolt Core") and my Bolt installation shows 1.2.0 for all three plugins. The Bolt Update Wizard says there are no updates available and manually importing from the Asset store yields a "No Imports Available" window. So somehow we're both at the "latest" version, but the version numbers for 2 of the plugins differ. Not sure if that can be related the cause of this error or not.
Anywho, we were able to stop the infinite generation of Scene Variable instances by quitting out from Unity. After re-opening and manually deleting the hundreds/thousands of extra instances, we were able to create a new instance of Scene Variables by right clicking to open the fuzzy finder. Each time we opened the FF, it would generate another instance.
The infinite generation occurred only when we created a "Get Graph Variable" block and then the second we switch it to the Scene level it starts (and shows "Error" in the string field). Deleting this block stops the infinite generation.
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