No highlighter with name or type 'Html' registered

Summary: Bug NCBC-1523 fixed one issue, but another one has come up in its place. An error message "no highlighter with name or type 'Html' registered" is being returned by the .NET client (but query still works fine in Couchbase Console)

Repro: I'm using the .NET SDK with the fix for NCBC-1523 (revision 5bd99cd6c056e624e1487aec3d40640f43f33922 from review.couchbase.org/couchbase-net-client) with the same code and FTS index as in -NCBC-1523-

Expected: Search results (with highlighted HTML)

Actual: Error message: "no highlighter with name or type 'Html' registered"

Notes: I suspect it might be something like a casing issue (e.g. server is expecting "html" but is being passed "Html" or vice versa). However, I cannot get WireShark to collect any data for me.