incognito mode with Chrome runtime

[naoki5]

My application implements “incognito mode” by setting CefSettings.cache_path to empty.
This behavior is described in cef_types.h.

https://github.com/chromiumembedded/cef/issues/3685
I have migrated my application to Chrome bootstrap + Alloy style.
Then, even if cache_path is empty, the cache data is still stored.
It appears to be stored in the following location.

C:\Users\username\AppData\Local\CEF\User Data\Default

cefclient works the same way.
Disabling Chrome runtime makes it work in incognito mode.

cefclient.exe --disable-chrome-runtime

Is this behavior a Chrome runtime specification?
How can I implement incognito mode with Chrome bootstrap?


CEF 127.0.20 Windows 32-bit
Windows 11 Pro 23H2 (Japanese)
Visual Studio 2022 Version 17.10.5
Win SDK 10.0.22621.3233

[magreenblatt]

Cache data will still be stored, however profile data will not. See the documentation.

[naoki5]

I did not understand the documentation correctly.
With Chrome runtime, does this mean that data is always stored on disk?
Does this mean that it is no longer possible to set it to incognito mode?

[magreenblatt]

There is a difference between cache and profile data. “Incognito mode” means that profile data is not stored on disk. See https://chromium.googlesource.com/chrom ... ata_dir.md

[naoki5]

I think I understand most of it.
Thanks.

I was hoping that cache, history, cookies, etc. would not be stored and it worked that way with Alloy runtime.
With Chrome runtime it is stored in “Default” and I need to remove it.

[TaurusPrime]

Hi,

I don't understand the solution.

So, we have:

Code: Select all

// Specify CEF global settings here.
CefSettings settings;
CefString(&settings.root_cache_path).FromWString(root_cache_path);
CefString(&settings.cache_path).FromWString(L"");

and in OnBeforeCommandLineProcessing:

Code: Select all

command_line->AppendSwitch("incognito");

But still there are a lot of files in "C:\Users\username\AppData\Local\CEF\User Data\Default".

Most scary is History in "Default". URLs can be seen in clear text.

So please, how to use the chrome-built-in incognito with CEF for a save browser experience?

Btw: looks like a bug. V126 with use_views is working. V132 is not working.

[Rister]

Hi,
Btw: looks like a bug. V126 with use_views is working. V132 is not working.

Probably the issue at github is also yours according to the username

I noticed this in cef 131 (0.6778.265). Maybe if we can bisect this into some concrete version after V126 but before V131 range, the developers will be able to fix it quickly.

[magreenblatt]

The "Default" profile is always created by default but will only be used for non-incognito browsers.

[Rister]

The "Default" profile is always created by default but will only be used for non-incognito browsers.

Ok, probably some new/hidden logic introduced sometime before, but the documentation and all other info that can be found on the web shows that "if the cache_path is empty then the user data will be in memory" logic never changed and it should still work. Can you point out to a commit/discussion/doc page that shows that one now has to take something else into account if he or she wants to start in basically incognito mode?

[magreenblatt]

The documentation is correct. If cache_path is empty an incognito profile will be used.