Fixed an issue with the insertBefore method that was causing children…

[maximtwo]

… of a container to sometimes be in an indeterminate order after re-ordering.

Description of change

Fixes: #422

Pre-Merge Checklist

• [x] Tests and/or benchmarks are included
• [x] Documentation is changed or added
• [x] Lint process passed (npm run lint)
• [x] Tests passed (npm run test)

[codesandbox-ci[bot]]

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Sandbox	Source
sandbox	Configuration
dreamy-wildflower-sorf1z	Issue #422
cranky-butterfly-o43bxc	Issue #422