Bug fixes:

• [fastproxy] Do not read response body for HEAD requests (#11442 by kevinpollet)
• [metrics,tracing,accesslogs] Fix observability configuration on EntryPoints (#11446 by rtribotte)
• [webui] Set content-type when serving webui index (#11428 by kevinpollet)

Documentation:

• [acme] Fix deprecated dnsChallenge propagation logging and documentation (#11433 by thomscode)
• [acme] Add missing trailing s to propagation.delayBeforeCheck option (#11417 by jspiers)

Misc:

• Merge branch v2.11 into v3.3 (#11419 by kevinpollet)