Edit cells doesn't work after selecting a sheet

Steps to Reproduce

1. load the attached file with 5.0.0.FL.20191211-Eval
2. select the 2nd sheet
3. set C3 background color with red

Current Result

C3 background doesn't change

Expected Result

C3 background should change to the specified red

Debug Information

• any edit operation doesn't work on the 2nd sheet because there is no onZSSSynncBlock event fired to the server

Workaround

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