Most caching libraries don't do locking, meaning that >1 process can be calculating a cached value at the same time. Since you presumably cache things because they cost CPU, database reads, or money, doesn't it make sense to lock while caching?
This is a fork of https://github.com/SortableJS/angular-sortablejs that allows to set which parent container for sortable elements. This fixes issues with material components, such as mat-chip-list, that wrap their elements.