For the 64-bit 2020 version
I tried in vain to find the current location of this file for version 2020. When navigating to Help > Edit Custom Properties
a new (empty) file is created at appData/Roaming/JetBrains/IntelliJIdea2020.1/idea.properties
. There is no /bin directory as some tutorials suggest. However, neither adding the block from the accepted answer to this file nor adding the same file to /bin resulted in an update to my configuration.
I finally discovered that a reference to the same property exists in appData/Roaming/JetBrains/IntelliJIdea2020.1/idea64.exe.vmoptions
. It looks like this:
-Didea.max.intellisense.filesize=3470
I changed it to this, which should be adequate for my needs:
-Didea.max.intellisense.filesize=9999
This strikes me as a bug in this version where the behavior of the menu item doesn't reflect what's needed, but it may also be the case that my particular setup is somehow different than stock. I do have PyCharm and the JDK installed.