The Beta channel has been updated to 21.0.1180.81 for Mac, Linux, Windows and Chrome Frame

This build fixes the following issues:

• Duplex Printing defaults to Yes, which prints extra pages even for a 1 page print out (Issue 138312).
• Print preview takes forever on Win XP (issue: 140044)
• Anti-DDoS inversion of logic (Issues: 141643, 141081)
• Pepper Flash: in file uploads, treats HTTP status != 200 as failure, breaking (e.g.) uploads to Amazon S3 (Issue: 140468)
• Projectmanager.com application causes Flash to hang (Issue: 141018)
• Turn off TLS 1.1 in Chrome 21 Stable (Issue: 142172)
• An additional scroll bar appears at the right on many sites (issue: 140239)
• Setting and unsetting display:none obliterates current scroll position (issue: 140101)