This release adds css.Build, native and very fast bundling/transformation/minifying of CSS resources. Also see the new strings.ReplacePairs, a very fast option if you need to do many string replacements.

• Upgrade to to Go 1.26.1 (#14597) (note) 1f578f1 @bep #14595. This fixes a security issue in Go's template package used by Hugo: https://www.cve.org/CVERecord?id=CVE-2026-27142

The methods and config options are deprecated and will be removed in a future Hugo release.

Also see this article

• languageCode → Use locale instead.
• languages.<lang>.languageCode → Use languages.<lang>.locale instead.
• languages.<lang>.languageName → Use languages.<lang>.label instead.
• languages.<lang>.languageDirection → Use languages.<lang>.direction instead.

• .Site.LanguageCode → Use .Site.Language.Locale instead.
• .Language.LanguageCode → Use .Language.Locale instead.
• .Language.LanguageName → Use .Language.Label instead.
• .Language.LanguageDirection → Use .Language.Direction instead.

• tpl/css: Fix external source maps e431f90 @bep #14620
• hugolib: Fix server no watch 59e0446 @jmooring #14615
• resources: Fix context canceled on GetRemote with per-request timeout 842d8f1 @bep #14611
• tpl/tplimpl: Prefer early suffixes when media type matches 4eafd9e @bep #13877 #14601
• all: Run go fix ./... e310822 @bep
• internal/warpc: Fix SIGSEGV in Close() when dispatcher fails to start c9b88e4 @bep #14536
• Fix index out of range panic in fileEventsContentPaths f797f84 @bep #14573

• resources: Re-publish on transformation cache hit 3c980c0 @bep #14629
• create/skeletons: Use css.Build in theme skeleton 404ac00 @jmooring #14626
• tpl/css: Add a test case for rebuilds on CSS options changes 06fcb72 @bep
• hugolib: Allow regular pages to cascade to self 9b5f1d4 @jmooring #14627
• tpl/css: Allow the user to override single loader entries 623722b @bep #14623
• tpl/css: Make default loader resolution for CSS @import and url() always behave the same a7cbcf1 @bep #14619
• internal/js: Add default mainFields for CSS builds 36cdb2c @jmooring #14614
• Add css.Build 3e3b849 @bep #14609 #14613
• resources: Use full path for Exif etc. decoding error/warning messages c47ec23 @bep #12693
• Move to new locales library and upgrade CLDR from v36.1 to v48.1 4652ae4 @bep
• tpl/strings: Add strings.ReplacePairs function 13a95b9 @jmooring #14594
• github: Remove pull_request_template.md 54c8048 @bep
• testing: Make commands tests pass in Go 1.26.1 157bfdd @bep
• refactor: Deprecate language configuration and template methods d4f2122 @jmooring #14269
• Replace Exif with Meta in tests 991d2f9 @bep
• resources: Improve getImageOps error message e857777 @jmooring #14571
• resources/images: Add IsImageResourceWithMeta etc. tests for bmp and gif 44dc384 @bep #14568

• deps: Upgrade github.com/evanw/esbuild v0.27.3 => v0.27.4 0e46a97 @bep
• build(deps): bump github.com/getkin/kin-openapi from 0.133.0 to 0.134.0 c27d9e8 @dependabot[bot]
• build(deps): bump golang.org/x/tools from 0.42.0 to 0.43.0 098eac5 @dependabot[bot]
• build(deps): bump gocloud.dev from 0.44.0 to 0.45.0 87f8de8 @dependabot[bot]
• build(deps): bump golang.org/x/sync from 0.19.0 to 0.20.0 67ef6c6 @dependabot[bot]
• build(deps): bump golang.org/x/net from 0.50.0 to 0.51.0 (#14569) b29c2f7 @dependabot[bot]
• build(deps): bump github.com/tdewolff/minify/v2 from 2.24.9 to 2.24.10 (#14585) e91d191 @dependabot[bot]
• build(deps): bump github.com/bep/imagemeta from 0.15.0 to 0.17.0 (#14584) a8a54bd @dependabot[bot]