Windows, out-of-source:
mvn compile exec:java '-Dexec.mainClass="org.unicode.text.tools.Indexer"' -am -pl unicodetools "-DUNICODETOOLS_GEN_DIR=Generated" "-DUNICODETOOLS_REPO_DIR=." "-DCLDR_DIR=..\cldr\"
Upload Generated\charindex.html and Generated\charindex-draft.html to https://www.unicode.org/charts/charindex.html and https://www.unicode.org/charts/charindex-draft.html.
[!CAUTION] The tool also generates a file at Generated\fr\charindex.html based on the French NamesList.txt. This French version of the index has major searchability shortcomings, and a considerable amount of untranslated English. It should not be deployed at this time.