showModalDialog is a terrible API, both to implement and to use. And it's relatively little used on the web. We should try to remove the last remaining usage by warning in the developer console whenever it is used. Chrome just did the same so we're not going alone.
This should be trivial, we just need to call ReportUseOfDeprecatedMethod() in nsGlobalWindow::ShowModalDialog() here, and set the message up for localization etc.
We also have WarnOnceAbout() which appear to have the same purpose as ReportUseOfDeprecatedMethod(). I filed bug 933563 on consolidating them :)
I would like to work on it.
ups I am sorry Ritesh. I have done it meanwhile.
Comment on attachment 826031 [details] [diff] [review] bug933040 Stealing review, and thanks vendo! r=jst
Created attachment 826265 [details] [diff] [review] bug933040 lower case applied
Comment on attachment 826031 [details] [diff] [review] bug933040 I'd say simply refer to window.open instead. showModalDialog() doesn't provide much value over what window.open does, other than that it's synchronous, and the synchronous part is not something that any frameworks can help with.
Created attachment 826925 [details] [diff] [review] bug933040 ok, patch updated
4 years ago
FWIW, I also filed bug 933042 on making WarnOnceAbout collect telemetry so that we know if/when it's safe to remove the implementation.
I guess this patch is ready to be checked in then.