Digital goods, such as installable software applications, including web applications and browser extensions can be offered to users.  The digital goods can be offered within in a designated online marketplace for web applications and extensions, and they can be offer from other online locations other than the designated online marketplace.  When digital goods are offered for sale or for free download in a marketplace the goods can be listed in the marketplace by a developer of the goods, and the marketplace can offer a forum to the developer within which many users can discover the developer's goods.  In addition, the marketplace can collect payment for the goods from purchasers of the goods and then can pass on the payment to the developer of the digital goods. 
A store operating as a marketplace has many desirable properties compared to a store operating as a seller of record or as a reseller, in which the reseller purchases goods from developers and resells them at a price determined by the reseller.  A marketplace operator may have less liability for the performance of the goods that are sold and has the opportunity to be more inclusive of goods that can be offered in the marketplace.  However, the marketplace operator may nevertheless want to ensure that the digital goods conform to certain quality standards and did not pose a threat to the consumers of the goods.  On the other hand, the marketplace operator may want to make the process of listing a good in the marketplace as easy as possible for a developer of the good. 
In addition, a party that has a stake in the performance, security, reliability of the web applications and browser extensions, including a host of an online marketplace for the web applications and browser extensions, generally may want to ensure that users of the web applications and browser extensions use high performance, secure, and reliable web applications and browser extensions, or at least that users are aware of any concerns regarding the performance, security, and reliability of web applications and browser extensions that they use.