Security Level: Jimmy
Run attached sample.
Load page, open developer tools in browser
navigate to sheet2
(if error doesn't happen switch from sheet1 and shee2 a few times)
(if still doesn't happen, reload page and try again from start)
Caused by both client and server-side interactions
When loading blocks in a page with frozen top row(s), the spreadsheet _visibleArea at server side top boundary is set to the non-frozen first row.
(if rows 1 to 4 are frozen, row 5 is the top boundary of the _visibleArea)
During sheet selection, the data returned for the selected sheet is based on the current _visibleArea:
At this point, the visible area is used to find the top boundary of the data to return to client.
This cause client to receive data missing the top X rows, where X is the number of frozen rows in the previously selected sheet
Send an syncBlock request to force the server's _visibleArea to include the frozen rows on top of the current sheet if any before the processing the data request for the new page.