Uninstalled 5.1.6, then tried to reinstall the latest version (5.1.7) from scratch, and got this error:
Installing Plugin: Wordfence Security 5.1.7
Downloading install package from https://downloads.wordpress.org/plugin/wordfence.5.1.7.zip…
Unpacking the package…
Could not copy file. wordfence/screenshot-5.png
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