2.2.42 [HTML5:2014] Section 5.6.11 Unloading documents
C0058: The prompt does not show the returnValue
The specification states:
... Unloading documents ... When a user agent is to prompt to unload a document, it must run the following steps. 1. ... ... ... The prompt shown by the user agent may include the string of the returnValue attribute, ...
All document modes (All versions)
The prompt does not show the