I'm on MediaWiki 1.33 using the MobileFrontend skin. The default parameter buttons do not go away when you replace them with one's own parameters. Instead, the ones specified are just added to the default buttons and you end up with two buttons for some services
Topic on Extension talk:AddThis/Flow
Appearance
My solution so far has been to just hide the buttons using CSS selectors
.at300b:nth-child(2), .at300b:nth-child(3), .at300b:nth-child(4), .at300b:nth-child(5), .at300b:nth-child(6), .at300b:nth-child(7), .at300b:nth-child(8), .at300b:nth-child(9), .at300b:nth-child(10){ display: none; }
My solution was to replace AddThis.php by one from older version for MW 1.30