nuxeo-wopi addon does not declare any package dependencies. However, it obviously depends on nuxeo-web-ui, since the latter includes the strings used for tooltips: wopiLink.* in i18n/messages.json, that ends up in nuxeo.war/ui. These tooltips are generated also in that package: see _wopiTooltip.
This raises the question, when I want to prepare a simple addon atop of the nuxeo-wopi (so my addon depends on it), how do I provide more strings to the nuxeo.war/ui/i18n/messages.json? My package does not include any jar packages, and only adds some icons to ${env.home}/nuxeo.war/ui/images, and a config to ${env.config}, using copy scripting command.
But there seems to be no scripting command to extend existing json files; adding another json file to that directory is ignored by nuxeo; and manually editing the json gets overwritten on server restart.
What is the correct way to add some strings to nuxeo.war/ui/i18n/messages.json when installing a simple addon?