Maxthon and Avant scandals?

Testing has revealed that versions 1.2-1.5 of the Maxthon browser modify the user agent string of IE and other IE-core based browsers by adding the Maxthon identifier, regardless of whether the Maxthon browser is running or not. A similar situation was also observed with the Avant Browser. If these two browsers are installed or used interchangeably, user agent strings such as "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; Avant Browser; Maxthon; Avant Browser; .NET CLR 1.1.4322)" may appear.