What is the expected encoding for Resource Bundles?

[Former Member]

I'm loading a ResourceModel as follow and using data binding from the view to retrieve text associated to a key.

var iModel = new ResourceModel({ bundleName: "app.i18n.ui5resources" });<br>this.getView().setModel(iModel, "i18n");

app.view.xml:

<Text id="titleText" text="{i18n>main.appview.title}"/>

The properties file "ui5resources.properties" is ISO8859-1 encoded as suggested in the Development Conventions and Guidelines documentation.

It does not work for characters in the range [80-FF] in that encoding.

I know I can use Unicode Escape notation for non-ascii characters (\uxxxx). However, it looks like it is also working with UTF-8 encoded file.

UTF8 would be the preference for our l10n teams as it does not require to convert the file. Is UTF-8 officially the encoding to use?