VST2 Issues

Considering the amount and nature of open VST issues, I believe a meta issue is in order.

Enhancements

• Idea for re-establishing VST-based LMMS-preset 'pre-hear' #5039 (PR: #5441)
• VST Scan system, multiple folder selection and some other things (#1837, #4907) [Milestone: 1.3]
• Preserve plugin state when VST fails to load #4850
• Embedded plugins hide UI by default #4834
• Remove "Sync VST plugins to host playback" option #4730
• Show all installed VSTi plugins in the Instrument Plugins sidebar #4585
• Add error messages if VST loading failed #4447
• Add native VST support for Mac OS X (WIP) #3975
• Multiple MIDI channels for a single VSTi #1178
• opening a VST preset should not open the VST GUI #2143
• Distinguish between VSTi and VST-FX #2003 [Milestone: 1.3]
• Add Steinberg locations to VST search paths #1808 [Milestone: 1.3]
• VST plugins on OS X (Apple) #698
• LinuxVST support #416 [Milestone: 1.3]
• Can better automation-track labels from VSTs be implemented? #415
• VST controller knob search #308 [Milestone: 1.3]
• 64 bit VST on Linux/Wine #4103
• Support shell plugins (#5542, maybe #6337)

Bugs/Misc

• Opening VST Controls crashes LMMS #5966 [Milestone: 1.3]
• RemoteVstPlugin fails to build with with -flto #5179
• LMMS clumsily interacts with VST #4828
• CPU overload when loading a project with specific VST's #4788
• Error Loading Plugins #4619
• (Suggestion) Background Process for Checking Crashes / Other LMMS Background Processes #4408
• "Stay on top" bug when project contains VST effects #4183
• VST changes preset value on load #3847
• Not loading banks (.fxb) properly #705
• VST UIs do not scale on HiDPI screens (#4411, #7683)

Crashes/Freezes

• RemoteVstPlugin.exe.so crashes lmms on "incompatible Qt library" #5302 (Source)
• Crashes when pushing through MIDI input while cloning a Vestige TCO #5015 [Milestone: 1.3]
• All VSTs are freezing LMMS in a minute or two (Linux, master) #4885 (XEmbed only) [Milestone: 1.3]

Specific VST issues

• High CPU usage with the Piapro Studio VST at Idle #5353
• Kontakt is buggy in LMMS (Explanation in Description) #4087
• Issue with Vestige + Helm #3918 [Milestone: 1.3]

I'll try to keep this relatively organized and limited to VST2-exclusive bugs. If there are issues you believe should be added, removed, or recategorized in the list, please say so!

Review the linked VST issue list and its Enhancements, Bugs/Misc, Crashes/Freezes, and Specific VST issues sections first. Done means keeping this meta issue organized and updating entries as related work is added, removed, recategorized, or completed; no source file or test is identified.