The multinational has gradually changed its policy regarding browser extensions to avoid abuse. Last year he forced all Chrome extensions for Windows were hosted on the Chrome Web Store, a change that reduced user requests for information to uninstall unwanted extensions by 75 percent. Measure did not apply to windows developer channel but hackers are now using it to install the extensions.
Therefore, since last Wednesday, all extensions for Windows must be in the Chrome store, and the same will happen with extensions for OS X, but will apply in July.
Google automatically scans extensions that show suspicious behavior. Most are later published, although some may be retained for manual review. In general, extensions that interfere with ads, for example, or that are considered spam, are generally prohibited.
To the developers, Google still allows them install extensions locally, as well as those installed through a group policy.
In order not to harm the user experience, Google also allows so-called inline installations, where the user can install an extension directly from a web page, but it is actually hosted on their web store.