WiX Online Meeting 310 Highlights

With more than 300 meetings under our belts, earlier this month the WiX Toolset YouTube channel turned 13 years old! We began lovingly hand-writing these meeting highlights a year and a half later. As an official teenager, you can expect the channel to go through mood swings and start to test boundaries and break a bunch of dumb rules, fighting for its right to party. We expect the channel to quickly mature and buckle down on its studies.

Issue triage

Add option to suppress hard linking, from @NeoAdonis, was revived when a FireGiant customer pointed out that the fix was partial: Files created by WiX itself (as opposed to by the WiX MSBuild targets) still sometimes use hard links. Rob volunteered to fix the bug end to end.
RegisterProduct writes ARP entry to HKLM for a perUserOrMachine package even though MSI_LUA selects per-user mode and clears ALLUSERS, from @aliwasif177, says it’s a bug that a perUserOrMachine package writes its Uninstall key to HKLM even when installed in per-user mode. We don’t disagree because a “pure” per-user package does so. But maybe MSI had a good reason (or even just a bad reason) for using HKLM. In any event, it’s under MSI’s control and WiX can’t force MSI to do its bidding. (Oh if only!)
Screen readers do not announce descriptive information for the ‘Change’, ‘Repair’ and ‘Remove’ button in windows., from @msftedad, is a report of a lack of accessibility support in Windows Installer internal UI. Unfortunately, internal UI hasn’t much changed since early this millenium and accessibility support is limited.
WiX MSBuild targets do not expose -nostdlib, from @barnson, from some whinging user who wants to be catered to. Oh wait, it was me. The -nostdlib is rarely needed so exposing an MSBuild property is overkill. Even I agree with that. I should have just closed the bug before the meeting to avoid exposing myself but I forgot. So this is my punishment.
Even when -nostdlib is specified, WiX adds a reference to it, from @barnson, is a slightly less whinging report but after discussing the issue, I came to agree with Rob’s idea that if you use -nostdlib, you’re doing something advanced enough to need to follow the rules.
Allow Burn bundles to downgrade installations, from @reflectronic, requests language support to override Burn’s default of blocking attempts to downgrade bundles. Given that downgrading packages is a challenge—Windows Installer really doesn’t want to downgrade something once it’s installed—blocking downgrades was an explicit choice. A bootstrapper application can override that so the scenario is still possible, just with a bit of extra effort. It’s not the first feature that’s available only with BA support and it won’t be the last. Probably.
CopyFilesToOutputDirectory task fails when output path is relative in multithreaded build (-mt switch), from @philipp-naused, reports that the new MSBuild support for multithreaded builds—distinct from its long-extant support for multiprocess builds—doesn’t work 100 percent with WiX MSBuild tasks. Multithreaded MSBuild is new to .NET 11 and isn’t complete yet but we know it’s coming in the November release of .NET, so Rob volunteered to investigate.