After an upgrade of LUNA sometimes the LUNA Viewer will look strange or not display as expected. This is happens when we make substantial changes to the HTML and CSS. Some of these files are stored in your browser cache. By default we cache files for 7 days. So if a user accesses LUNA within 7 days before and after an upgrade they may see this problem and would need to clear their browser cache to fix the problem. We will describe how you can change this cache to 5 min instead of 7 days.
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After you have done this, restart LUNA's tomcat.
When 7 days have passes passed, after the upgrade, you can change this value back and restart tomcat.
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