Crash adding Measure Segments LPE if path has single point subpaths

Steps to replicate

• open crash_measure.svg in Inkscape
• select the I path (or create a path and change the d value to M 131.45652,95.064161 76.467183,130.26395 m 15 15 z
• open the LPE dialog
• Add the Measure Segments LPE

What happened?

• Crash, backtrace from comments inkscape_backtrace_measure_empty.txt

What should have happened?

• No crash

Version Info

• Inkscape 1.1 Windows 10
• Replicated alpha0 appimage, Inkscape 1.2-dev (5f01de93, 2021-08-06) Linux Mint 20 (from comments)

Original report

Hi

I am experiencing a crash after using Instant Path Effect > Measue Segments

The problem occurs with the following typeface: Albertus Extra Bold