Spreadsheet with mostly hidden rows and columns looks strange

[thebearon]

In the attached spreadsheet, rows 16+ and columns H+ are hidden.

hidden_rows_and_columns.ods

In LibreOffice desktop, simply the range A1:G15 is shown. In Collabora Online it's shown as follows:

Problems:

• row 1 is wrong,
• rows and columns have gridlines that go on even when the remainder of the sheet is hidden,
• the background color of visible and hidden areas is the same.

[ototo]

It gets even trickier when one column and one row are frozen.

[heyrict]

Confirmed this bug also occurs on android 10, collabora office 23.05.4.1