Five dated news digests and five engineering Q&A entries. Each item cites primary documentation or release artifacts (not generic placeholders).
The jQuery blog announces 4.0.0 beta with removals (deprecated APIs, JSONP auto-promotion) and compatibility guidance for projects still on 3.x.
Teams should read the upgrade guide before flipping majors in enterprise portals.
The follow-up beta post highlights compatibility refinements and contributor-facing testing changes that reduce flaky CI when bisecting regressions.
Validate CSP policies with Trusted Types enabled during the beta period.
The official upgrade guide enumerates breaking changes such as focus/blur event ordering alignment with the DOM spec and removal of automatic px appends.
Use jQuery Migrate temporarily if you need telemetry on removed APIs.
jQuery remains under OpenJS governance; security disclosures should follow the documented reporting process while upgrades roll out.
Correlate npm advisories with tagged releases.
Release assets and tags on jquery/jquery provide checksums used by CDNs and package mirrors.
Mirror internally only after verifying integrity attestation policies.
The beta announcement documents browser support changes; IE10 and older are out, while IE11 remains for 4.x with removal slated for jQuery 5.
Plan polyfills accordingly if intranet apps still require IE11.
Explicitly request JSONP endpoints or migrate to CORS-enabled JSON; the upgrade guide notes the removal of automatic JSONP promotion from AJAX responses.
Audit legacy ad tags that depended on the old behavior.
jQuery Migrate remains the supported compatibility shim to surface warnings for removed APIs before they fail hard.
Remove it after warnings reach zero in CI logs.
The upgrade guide calls out that jQuery no longer appends px to unitless numeric CSS values—use explicit units in your code.
Search for .css("height", number) patterns in legacy widgets.
Use the maintainers’ documented security contact on jquery.com and avoid filing public issues until patched releases ship.
Include minimal reproduction HTML without user secrets.