If you want to run the latest prerelease version of a Zotero component (e.g., to take advantage of a recent bug fix or test a new feature), you can install a dev build. These versions are built regularly and may be less stable than release versions.
(If you want to make code changes, see Zotero Source Code.)
Beta versions of Zotero are currently built from the development line for Zotero 5.0 and contain changes made since the last 5.0.x release.
Beta versions will update automatically. You can update to the latest version at any time via Help → Check for Updates. To revert to the release version, simply reinstall it from the download page. Your data won't be affected.
Beta versions of the Zotero Connector are available for Firefox:
Beta versions will update automatically, or you can update to the latest version at any time from the Firefox Extensions pane. To revert to the release version, simply reinstall it from the download page.
Beta versions are not currently available for Chrome or Safari.
Not currently available