I have the same problem.
Please advise if I’m wrong with my statements.

i guess the file you mention is called BCUEngine-trace.log and is in the directory C:\ProgramData\AVAST Software\Avast\log

The only content you (or at least I) find looks like this below.

I also do believe, that the problem comes from one of my only 3 plugins I have installed:

  • Avast Online Security (if this would be the case, then please fix the bug :P)
  • Avast Safe Price (looks like I will already deactivate it 8))
  • NoScript (but please, if this would be a dangerous plugin, then you are just paranoid :o)

I certify - no other plugin or extensions are activated.

Would be curious to know if anybody else can confirm this.

19.12.2017 22:59:49 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll Init()
19.12.2017 22:59:49 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll CheckCache()
19.12.2017 22:59:50 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll LoadExtensions()
19.12.2017 22:59:57 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll GetInstalledBrowsers()
19.12.2017 22:59:57 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll FreeString()
19.12.2017 22:59:57 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll GetProtectorInfos()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll GetDataFromBackend()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll FreeString()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll GetExtensions()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll FreeString()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll GetBrowserProperties()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll FreeString()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll IsSearchproviderHijacked()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll UpdateCache()
19.12.2017 22:59:58 ProcessId: 2416 ThreadId: 12976 From: c:\program files\avast software\avast\defs\17121604\bcuengine.dll DeInit()