Lines are bars

The progression box reads one line as one bar. Every non-blank line you type is a single bar of time, and the chords on that line share it equally: one chord alone on a line holds the whole bar, two chords split it in half, four chords each take a quarter. Empty lines, [Section] labels and | bar marks are ignored, so you can paste a chord chart in almost exactly as it's written and it lines up.

This is what lets a real chart work without reformatting. A line like [Verse] disappears, a blank line between sections disappears, and the | you use to separate bars is just stripped — only the chords and their line breaks decide the timing.

Example. Typed on four separate lines, Am, C, G, Dm are four bars, each chord held a full bar. Typed as a single line Am C G Dm, they're one bar with each chord squeezed into a quarter of it. And C G Am F on one line is one bar of four quick chords, while the same four on four lines is a slow four-bar loop.