Cannot get log4javascript to work with an InPageAppender when using requirejs

Cannot get log4javascript to work with an InPageAppender when using requirejs

If I use log4javascript without requirejs, everything (including in-page
appenders) works as expected.
When using requirejs, this works (a pop-up window appears with the warning):
var log = log4javascript.getDefaultLogger();
log.warn("This is a test error message.");
but this doesn't work (no in-page area is displayed):
var log4j = log4javascript.getLogger();
var log4jInPageAppender = new log4javascript.InPageAppender();
log4j.addAppender(log4jInPageAppender);
log4j.warn("This is a warning!");