Problem with global static attribute: Cef.IsInitialize

[PCX985485635]

Is there an existing issue for this?

• I have searched both open/closed issues, no issue already exists.

CefSharp Version

131.3.50

Operating System

Windows 10

Architecture

x64

.Net Version

.Net Framework 4.8

Implementation

WinForms

Reproduction Steps

Problem with global static attribute: Cef.IsInitialize:
When I was using the old version [109.1.110], I used multiple exe clients that worked, but after updating to the new version [131.1.50], I made some code changes:
Change 'if (! Cef. IsInitialize d)' to 'if (! Cef. IsInitialize d. HasValue | |! Cef. IsInitialize d. Value)'

When I open multiple exe clients, the error message is as follows:
Cef.Initialize can only be called once per process. This is a limitation of the underlying CEF/Chromium framework. You can change many (not all) settings at runtime through RequestContext.SetPreference. See https://github.com/cefsharp/CefSharp/wiki/General-Usage#request -context-browser-isolation Use Cef. IsInitialized to check if Cef.Initialize has already been called to avoid this exception. If you are seeing this unexpectedly then you are likely calling Cef.Initialize after you've created an instance of ChromiumWebBrowser, it must be called before the first instance is created.

From the error message above, it can be seen that the new version [131.1.50] seems to have Cef. every time a new client is executed IsInitialize will be null, causing the execution of the 'Cef. Initialize (settings, performanDependency Check: true, browserProcessHandler: null)' code after the 'if' code to be re executed

Expected behavior

When I want to open multiple clients (exe programs), only one initialization will be performed. Cef.IsInitialize will only execute the following code if the first client checks as fasle and all other clients are true:
Cef.Initialize(settings, performDependencyCheck: true, browserProcessHandler: null);

Actual behavior

When each client is first opened, CefIsInitialize is false, causing CefSharp to initialize multiple times

Regression?

No response

Known Workarounds

No response

Does this problem also occur in the CEF Sample Application

Yes using WPF/OffScreen command line args

Other information

No response

[amaitland]

Converting to discussion as I believe it's working as intended. A new issue can be created if code changes are required.

From the error message above, it can be seen that the new version [131.1.50] seems to have Cef. every time a new client is executed IsInitialize will be null, causing the execution of the 'Cef. Initialize (settings, performanDependency Check: true, browserProcessHandler: null)' code after the 'if' code to be re executed

That sounds like the expected behavior to me. CEF now uses the Chromium process singleton, only a single process may access a cache path. See #4668

You need to implement IBrowserProcessHandler and pass an instance to Cef.Initialize.

CEF doesn't provide any sort of API to determine if another process already has access to the cache before calling Cef.Initialize. The method will return false if there's already a process using the cache.

When each client is first opened, CefIsInitialize is false, causing CefSharp to initialize multiple times

If Cef.Initialzie returns false then you cannot continue with trying to use CEF in that process.

You can use Cef.GetExitCode() to get more details at runtime.

Expected behavior

When I want to open multiple clients (exe programs), only one initialization will be performed. Cef.IsInitialize will only execute the following code if the first client checks as fasle and all other clients are true: Cef.Initialize(settings, performDependencyCheck: true, browserProcessHandler: null);

It's up to you to implement this behavior in your application. You can use IBrowserProcessHandler.OnAlreadyRunningAppRelaunch to communicate with your other application instance. Or you need to use a different cache path for the different instances.