IE8 is not supported though. (It will generally work, but if you have issues and want to raise support requests, the response is going to be "try it with a proper browser or IE9+")
The Documentation Link Nic Provided is for JIRA server and although the information is mostly the same there are some differences, so you will want to refer to the Cloud supported platforms list, and as Nic stated IE 8 is not supported:
In the past, Portfolio for Jira required a high degree of detail–foresight that was unrealistic for many businesses to have–in order to produce a reliable long-term roadmap. We're tur...
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