The worksheet: editing a thousand tasks without leaving the page

The worksheet is the product’s center: the whole MAT tree as one virtualized, editable grid that stays smooth past a thousand rows. It’s designed for the daily reality of a tracker — long sweeps of small edits — so every edit commits from the keyboard, in place.

Inline editing

Click a cell (or press e on a focused row) to edit status, percent, owner, weight, or dates inline. Edits save on commit (Enter, or picking an option) — no Save button, no page round-trip. Only leaf tasks accept a manual percent; computed levels show a ∑ and will explain themselves (see the rollups guide).

The keyboard grammar

Every key below is read from the same registry the app dispatches from, so this list cannot fall behind the product. In the app itself, press ? for the full sheet.

With a row focused:

• ↓ — move to the next row
• ↑ — move to the previous row
• → — expand the row, or step into it
• ← — collapse the row, or step out to the row above it
• Space — expand or collapse the row
• PgDn — move twenty rows down
• PgUp — move twenty rows up
• Home — jump to the first row
• End — jump to the last row
• Enter — open the row's panel
• E — edit the row's first cell
• O — open the row's full page
• X — select the row for a bulk change
• ShiftX — select every row between this one and the last you selected
• N — add a row below this one
• ShiftN — add a row inside this one
• M — move the row somewhere else
• Delete or Backspace — delete the row
• Esc — clear the selection

Activating a row never leaves the grid: an item with children expands, and anything else opens in a slide-over peek so the worksheet stays exactly where you were. Adding a row lands you in its name editor. While a cell is open for editing:

• Tab — move to the next cell in the row
• ShiftTab — move to the previous cell in the row
• Esc — discard the cell's edit and go back to the row

Views that don’t lie

Per-level expand presets (“to milestones”, “to activities”, everything) persist per project, and filtered views — by status, due window, attention, or phase — prune the tree to matches plus their ancestors while keeping numbers, shares, and editing exactly as in the full tree. A filter is a lens, never a different truth; the URL carries it, so any view is shareable.

Structure edits

Add, delete, move, and reorder from the grid — drag with the row grip or use the Move dialog for a keyboard/screen-reader path. Deletes are soft with an immediate Undo toast; restores land back at the remembered position with rollups recomputed. Bulk-select leaf tasks and update status, owner, or dates in one transactional sweep, also undoable.

Density

Three densities: compact (default), dense (more rows for big screens), and field — 44px glove-friendly targets and larger type for phones at the workface. The worksheet remembers your choice per browser.