Frozen Row + Ctrl+Home = Wrong Rows Showing

Describe the Bug

When you have a frozen row, Ctrl+Home seems to oddly interact.

The row #s below the frozen row don't update as they should.

Steps to Reproduce

In Calc:

Open FrozenRow.-.Test.A1.ZZ10000.ods.
Press Ctrl+End.
Press Ctrl+Home.
- Pay attention to row #s below frozen row.

Expected Behavior

The rows to show:

1 AFrozenHeader
---------------
2
3
4
5

Actual Behavior

1 AFrozenHeader
---------------
9961
9962
9963
9964

(Instead of Ctrl+Home going from row 10,000 back to the beginning... it seems to not move any "unfrozen rows" up.)

Video

CollaboraOnline23.05.6.2.-.Frozen.Row.Ctrl+End.Ctrl+Home.Wrong.Rows.webm

0–7 secs = Pressing Ctrl+End then Ctrl+Home
- No frozen rows. You can see it act normal.
7–10 secs = I clicked in A2 + Layout > Freeze Rows and Columns.
- This makes sure Row 1 = frozen.
11+ secs = Pressing Ctrl+End then Ctrl+Home.
- 1 frozen row. You can see:
  - Columns move fine.
    - Before: ZZ
    - After: A
  - 2nd row down ("unfrozen rows") don't move at all.
    - Before: 9961
    - After: 9961

Desktop

Collabora version: 23.05.6.2
OS and version: Windows 10
Browser and version: Chrome 120.0.6099.71 (Official Build) (64-bit)

Initially found during COOL Weekly Meeting:

COOLWSD version: 23.05.6.2snapshot (git hash: 636a726(E)) LOKit version: Collabora Office 23.05.6.20231214 (git hash: f6f27ac) Served by: Ubuntu 22.04.3 LTS (4e614eed)

I also reproduced on my local:

COOLWSD version: 23.05.6.2 (git hash: 4ea31bfe) LOKit version: Collabora Office 23.05.6.3 (git hash: 9a94664) Served by: Linux Mint 21.1 Server ID: 02d1ad25

This bug DOES NOT occur in LibreOffice:

Version: 7.6.4.1 (X86_64) / LibreOffice Community Build ID: e19e193f88cd6c0525a17fb7a176ed8e6a3e2aa1 CPU threads: 8; OS: Windows 10.0 Build 19045; UI render: Skia/Raster; VCL: win Locale: en-US (en_US); UI: en-US Calc: CL threaded

Additional Context

(I caught this one during COOL Weekly Meeting 148.)

CollaboraOnline / online

Frozen Row + Ctrl+Home = Wrong Rows Showing #7839