Beach balling freeze on huge library in v65.1 + v66.1

[TheBreznsoiza]

I recognize that Sketch freezes on huge library in v65.1 + v66.1, when I disable Artboard Manager those freezes are gone. I use a Material.io Baseline (abandoned) library, when I copy there a symbol sketch starts beach balling.

Same library v64.0 and enabled Artboard Manager works without problems. Already talked to Sketch support, in Safe Mode all worked fine, so I disabled most of plugins and figured out that Artboard Manager could cause this beach balling.

Can you take a look please, if someone has this problems too please confirm the bug. Thanks