Bridge CC 2018: Cannot get a TabbedPalette of type "web" (browser palette)

I have the problem mentioned in the title.


Here is the simplest example (copied quasi-verbatim from the Adobe Bridge CC 2018 Javascript Reference):

#target bridge

// create browser palette  

var webPalette = new TabbedPalette(app.document, "myWebPalette", "myWebID", "web", "http://www.adobe.com";);  

$.writeln("webPalette visible: " + webPalette.visible);

// create ScriptUI palette

var scriptPalette = new TabbedPalette(app.document, "myScriptPalette", "myScripID", "script");  

scriptPalette.content.add('statictext', [15,15,105,35], 'Display this text in my tab.');  

$.writeln("scriptPalette visible: " + scriptPalette.visible);  

I can run it in Adobe Extendscript Toolkit CC and the scriptPalette is created as expected in Bridge. Not the webPalette. I see no error message of any sort. The output on the console is as follows:

webPalette visible: undefined  

scriptPalette visible: true  

Hence it seems that the webPalette is not even created. Certainly it is not visible.

I believe this to be a bug.