gCodeViewer "skips" a layer

[b-morgan]

The attached file generated with Cura Lulzbot Edition (21.0.4) and Cura Lulzbot Edition Beta (2.6.21) for a TAZ 6 printer skips layer 7 when displayed with the gCodeViewer. It happens in multiple browsers (Firefox, Edge, IE, Chrome). Turning off the "Sort layers by Z" option will sometimes eliminate the issue. Note that layer 8 is actually the gcode of layer 7 so the following layer numbers are off by one.

Filament_clip_3mm_and_175.zip

The client computer is Windows 10.

[tsh-xx]

Ultimaker/Cura#2565 has another testcase. The workaround above works.

I observe OctoPrint has the same behaviour.

[b-morgan]

OctoPrint is using the same code as the gCodeViewer (without access to "Sort layers by Z" which is always on).