So I have a Vue app for a client set up on an apache dev server. I am doing this to match the production environment. The app is in a subdirectory and I set the \'base\' option
It can be a bug with your apache version.
RewriteRule of "^$" broke between 2.2.21 and 2.4.2 https://bz.apache.org/bugzilla/show_bug.cgi?id=53929
You can use Fallback ressource instead of mod_rewrite in your apache config. It works for me.
In /etc/apache2/apache2.conf
ServerName YourServerName
DocumentRoot /var/www/yourApp/dist
FallbackResource /index.html