What is this log mean? Do I need to take any action?
[Wed May 29 11:49:38.374 2019] [19141] WARNING: wordlist size mismatch (size=18, checkpoints=0)
[Wed May 29 11:50:45.875 2019] [19141] WARNING: wordlist size mismatch (size=18, checkpoints=0)
you could check your index data with indextool and skip this warning in case check passed well.
You also might create ticket at github there to put index data that cause this warning that helps to investigate issue.