@LesAHay, @Catweazle
New user of Vivaldi here! I just experienced the same issue, although it occurred about 10 minutes after installation.
Before accepting or denying anything, I did a search and came across this post! Being a curious software QA Engineer, I took a look in the Event Viewer and saw two Vivaldi-related events in the Defender Firewall logs at around the time of installation which had the "Action" listed as "Block". These rules were to allow inbound connections on all TCP and UDP ports.
On the Windows Defender Firewall popup window, I then selected to "allow" connections, and immediately six new events were added to the Event Viewer. Three dedicated to UDP with the "Action: Allow" status, and three dedicated to TCP with the same "Action: Allow" status.
The Windows event log is not the best for extracting data, so I tried to make something readable from the events in the log. Hopefully this will be of some use to somebody. I suspect that most users just click "allow" and go about their business and that's why nobody at Vivaldi is really aware of any "issue". That's what I would have done had I not had a bit of time on my hands! 😄
Events from time of installation:
Log Name: Microsoft-Windows-Windows Firewall With Advanced Security/Firewall
Source: Windows Firewall With Advanced Security
Logged: 02/10/2023 10:45:19
EventID: 2097
Task Category: None
Level: Information
Keywords: (2199023255552)
User: LOCAL SERVICE
Computer: <REDACTED>
OpCode: Info
---
A rule has been added to the Windows Defender Firewall exception list.
Added Rule:
Rule ID: TCP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Block
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: TCP
Security Options: None
Edge Traversal: None
Modifying User: NT SERVICE\mpssvc
Modifying Application: C:\WINDOWS\System32\svchost.exe
A rule has been added to the Windows Defender Firewall exception list.
Added Rule:
Rule ID: UDP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Block
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: UDP
Security Options: None
Edge Traversal: None
Modifying User: NT SERVICE\mpssvc
Modifying Application: C:\WINDOWS\System32\svchost.exe
Events following the selection of "allow" in the Defender Firewall popup:
Log Name: Microsoft-Windows-Windows Firewall With Advanced Security/Firewall
Source: Windows Firewall With Advanced Security
Logged: 02/10/2023 10:54:35
EventID: 2099
Task Category: None
Level: Information
Keywords: (2199023255552)
User: LOCAL SERVICE
Computer: <REDACTED>
OpCode: Info
---
A rule has been modified in the Windows Defender Firewall exception list.
Modified Rule:
Rule ID: UDP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Allow
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: UDP
Security Options: None
Edge Traversal: None
Modifying User: <HOST_REDACTED>\<USER_REDACTED>
A rule has been modified in the Windows Defender Firewall exception list.
Modified Rule:
Rule ID: UDP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Allow
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: UDP
Security Options: None
Edge Traversal: None
Modifying User: <HOST_REDACTED>\<USER_REDACTED>
A rule has been modified in the Windows Defender Firewall exception list.
Modified Rule:
Rule ID: UDP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Allow
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: UDP
Security Options: None
Edge Traversal: Defer to user
Modifying User: <HOST_REDACTED>\<USER_REDACTED>
A rule has been modified in the Windows Defender Firewall exception list.
Modified Rule:
Rule ID: TCP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Allow
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: TCP
Security Options: None
Edge Traversal: None
Modifying User: <HOST_REDACTED>\<USER_REDACTED>
Modifying Application: C:\Windows\System32\dllhost.exe
A rule has been modified in the Windows Defender Firewall exception list.
Modified Rule:
Rule ID: TCP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Allow
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: TCP
Security Options: None
Edge Traversal: None
Modifying User: <HOST_REDACTED>\<USER_REDACTED>
A rule has been modified in the Windows Defender Firewall exception list.
Modified Rule:
Rule ID: TCP Query User{<REDACTED>}C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Rule Name: vivaldi.exe
Origin: Local
Active: Yes
Direction: Inbound
Profiles: Private
Action: Allow
Application Path: C:\users\<REDACTED>\appdata\local\vivaldi\application\vivaldi.exe
Service Name:
Protocol: TCP
Security Options: None
Edge Traversal: Defer to user
Modifying User: <HOST_REDACTED>\<USER_REDACTED>