That’s not a webview, it’s a separate api with fewer abilities. Custom tabs I believe.
You can see for example that it always opens as a fullscreen overlay in your app and that it always has that bottom or in your case top bar.

.software seems quite expensive (and long to type).
njalla offers registering .software domains, so I would recommend them.

Feel like it’s less about the masonry and more about how Brandwand sounds quite silly

The kde default explorer dolphin does.
It creates them at the root of separate partitions (or maybe only network mounts).
Basically as a fallback to moving it slowly into a local trash.

You probably have the system mounted elsewhere and are accessing it remotely with dolphin would be my guess.

Last time I encountered it I found no good solution, it’s very anyoing.
Best workaround is to create a file of the same name as the folder, that way at least it stays empty.

Oh I misread.
Are you using Android 10+ and the op isn’t?

As best I can tell, Mull is us.spotco.fennec_dos, so on that list.
Mulch is likely us.spotco.mulch based on mulch webview being us.spotco.mulch_wv, neither are on the list.

My interpretation here is that Mulch uses some other system, perhaps that mentioned api or something else entirely. Therefore it needs no explicit mention and just works. It might be that it previously did not support that system, or bitwarden didn’t, but somehow now it does.
On the other hand, Mull still requires the manual compat lsit for whatever reason, therefore now in ironfox you run into that issue. In Mull it was likely solved before you ever used it.

deleted by creator

Maybe bitwarden has a hardcoded list of browsers and defaults to the app id otherwise? There could also be an override, but if not you’d have to open an issue with bitwarden and wait for them to update their list.

Edit:
Looking into the code there is indeed a hardcoded list.
This file contains the code

// Docs state that password fields cannot be reliably saved in Compat mode since they will show as
// masked values.
bool? compatRequest = null;
if (Build.VERSION.SdkInt >= BuildVersionCodes.Q && fillRequest != null)
{
    // Attempt to automatically establish compat request mode on Android 10+
    compatRequest = (fillRequest.Flags | FillRequest.FlagCompatibilityModeRequest) == fillRequest.Flags;
}
var compatBrowser = compatRequest ?? CompatBrowsers.Contains(parser.PackageName);

I read this as:
There are browsers that do “native” autofill and ones that do “compat”. Mull and ironfox do compat.
This compat support is communicated on Android 10+, but either on older android or maybe if the app is built for older android (?) it won’t be communicated, thus the hard coded list.

Doesn’t look like there is a way for users to add to this list.