Google this week began barring Chrome users from installing add-ons offered by third-party websites, the last steps toward making the company's own market the only available source for browser extensions.
"We continue to receive large volumes of complaints from users about unwanted extensions causing their Chrome experience to change unexpectedly - and the majority of these complaints are attributed to confusing or deceptive uses of inline installation on websites (emphasis in original)," James Wagner, the extensions platform product manager, wrote in a post to a company blog.
Inline installations originated as a convenience for add-on developers. Rather than direct their customers to the Chrome Web Store, developers were able to offer the extension from their own websites. The add-on was still hosted by the Store, but users weren't forced to leave the developer's site to install them.
Wagner spelled out the death of inline installation, saying it would take effect in three phases.
The first, which began June 12, banned inline installation of all newly-published extensions. Any that try will instead redirect to the Chrome Web Store, Google's e-mart for browser add-ons and Chrome OS apps.
Next, inline installations will be banned for existing extensions beginning Sept. 12. As in the first phase, users will be shunted to the Chrome Web Store to complete installation if that was initiated from another website. Chrome 69 should be the current version when this stage starts.
Finally, the install installation API (application programming interface) will be deprecated from Chrome 71, which is slated to ship the week of Dec. 2-8. In other words, the programmatic means to install an add-on outside of the Chrome Web Store will be eliminated.
"If you distribute an extension using inline installation, you will need to update install buttons on your website to link to your extension's Chrome Web Store page prior to the stable release of Chrome 71," Wagner warned.
The elimination of inline installation has been long in coming.
Google started its campaign to limit the sources of add-ons, and how they're installed, six years ago this month, when it first required that extensions move to the Chrome Web Store. With one step after another, Google tightened the screws with mandates that, for instance, blocked "silent" installations (February 2013), banned extensions not in the Chrome Web Store (May 2015) and purged add-ons that mine cryptocurrencies (April 2018).
All along, Google has contended that add-ons, while great at extending Chrome's functionality, were simultaneously a security nightmare-in-waiting unless they had been vetted, as they are before being allowed into the Store. Google also constantly claimed that users were disgruntled with add-ons they found outside the Store, and that such complaints tainted Chrome's reputation.
"When installed through the Chrome Web Store, extensions are significantly less likely to be uninstalled or cause user complaints, compared to extensions installed through inline installation," Wagner said.
More information about the demise of add-on inline installations - much of it aimed at extension developers - can be found on Google's website .