The previous Measure glyph was two icons sharing a box: a heavy closed ruler frame on the right and
two light caps on the left, with nothing relating them. It is now one instrument — two cursors
*standing on* the scale they read against, each marker centred on one of the scale's marks, so the
pair reads the way the pane works: bracket a window, read it against the axis.
Three things the render said, each fixed:
- **The closed frame was most of the ink.** Two lines and two end caps cost about a fifth of the
glyph's ink and say nothing a ruler's marks do not, so the scale is now one band with alternating
marks — long, short, long — hanging above it.
- **The caps were dashes, not grips.** 5x2 at 32px read as a horizontal stroke; they are 5x3, like the
caps on the toolbar's cursors icon.
- **The ticks were finer than everything else.** At 1px they were thinner than the 2px weight every
icon here uses, so they are 2px, and every mark alternates in height the way a ruler's do.
The Markers' shafts are dashed and meet the band rather than hovering over it, and the whole glyph is
inset two pixels like the others, so nothing is flush with an edge that a button's padding or a crop
takes a pixel off. Ink: 27%, inside the range the icons above it set.
Verified: `page icons: measure=udpscope-tab-measure-symbolic(ok) signals=udpscope-tab-signals-symbolic(ok)`;
`switcher: policy=narrow pills=2 labels=0 names=2 icon=32x32 size=308x36`; `[side-tab-probe] … advanced=4`;
the Preferences dialog opened in the same run with no "not present" (the plain ruler it uses is untouched);
`make test-ui` 14 files; zero `Gtk-CRITICAL`. The icons' blob is 12624 bytes, still over the C99 limit, so
the clean-build warning count stays four.