Selection model in mat-tree with checkboxes example not matching displayed selection · Issue #11400 · angular/components · GitHub
Does mat-tree support MatNestedTreeNode.level property? · Issue #17945 · angular/components · GitHub
ERROR Error: 'tree-viewport' is not a known element" error with Angular 9.0.0-rc.3 · Issue #770 · CirclonGroup/angular-tree-component · GitHub
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✓ NG8001: 'mat-icon' is not a known element: Error occurs in the template of component xxComponent. - YouTube
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