Feature Request: Keyboard Short-cuts

Here are additional keyboard short-cuts implemented in OpenOffice and Excel:

None are available using Firefox 68.0.1 (64-bit).

Using PgUp or PgDn currently scrolls the viewport without moving the active cell. This causes the active cell to be lost. From an end-user perspective, the active cell must always be displayed in the viewport, otherwise it is disorienting. This implies that Ctrl+Home and Ctrl+End also scroll the viewport to the top and bottom of the spreadsheet, respectively.

Similarly, when using the arrow keys, the active cell can be moved out of the viewport. When pressing the Up or Down arrow, if the active cell is at the top or bottom of the viewport, the viewport should scroll such that the active cell is always visible. (This could be configurable behaviour, preferably with tracking the active cell always on by default.)

Navigating a "page up" and a "page down" can be computed by the relation of the viewport height to the cell height. Jumping one page is equivalent to skipping over the number of rows visible in the viewport minus one. The maximum number of rows to skip can be set to a programmable limit (e.g., 30 rows).

Start by reproducing the listed keyboard-shortcut and active-cell viewport behaviors in the spreadsheet. Trace the existing keyboard navigation and scrolling behavior, then verify that the requested shortcuts work and that arrow-key, page, Home, and End navigation keeps the active cell visible.