With phpList 3.3.2 back in May, a new look for public pages was introduced. The default design was greatly improved but to avoid overwriting admin customisations, the improvements were not applied during phpList version upgrades so, only fresh installations of phpList with a new database could benefit from these improvements.
One of the improvements in phpList 3.3.4 is the “Reset style to default” option. This button gives you the opportunity to get the latest style updates for your subscribe pages on existing phpList installations.
Each subscribe page can be updated separately and a warning will be shown before you continue so, you don’t accidentally lose any style customization you may have made in your subscribe pages.
Updating the style for your default subscribe page will re-style other public pages of your phpList Installation. This is a handy functionality for easily applying any further enhancements that will be made in the future.