IMO, this has nothing to do with the number of runtimes. I mean; one runtime is only a list with one item. 15 runtimes is the same list, there's just, somewhere, 14 loops more, but the principle remain: from time to time, something is going wrong and the library window remains empty
It can be the database that didn't responded, leading to a unmanaged situation and an empty window for example.

I think that the Dev team should introduce a kind of switch somewhere, false by default. and if set to true, a more complete log file could be filled, helping the dev team to target some deep-hiding bugs, such as the one that makes the RTX Cycles-based engine crash for seemingly difficult-to-find reasons.
I develop all day long in Odoo's framework, a Python-based ERP, and there are some switches that can explode the log file, depending on its setting.

𝒫𝒽𝓎𝓁

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