Page URLs with high-ASCII characters do not purge

One of our customers discovered that pages that have extended (high) ASCII characters in the URL were not purging the Varnish cache. When we changed the URL to use only standard ASCII characters, the cache was purged immediately. When we changed the URL back to using a path with a high ASCII character, the page was not purged on save. We separately tested a curly apostrophe, a letter e with a grave accent, and curly double quotes.

Example:
/l’avant-scène-performs-“motifs” does not work.
/l-avant-scene-performs-motifs works.

Michael