12.3.4.3 Specifying the plug-in schema version for plugin.xml
To specify the plug-in schema version (not to be confused with the plug-in product version or the Eclipse version):
; PluginSchemaVersion = version used to validate plugin.xml.
The value of PluginSchemaVersion becomes the value of the version attribute in a processing instruction (PI) in plugin.xml; see §12.3.4.2 Including a processing instruction to validate plugin.xml.
If you do not specify a value for PluginSchemaVersion, the default value depends on the value of UseManifest:
• If UseManifest=Yes, PluginSchemaVersion=3.2.
• If UseManifest=No, PluginSchemaVersion=3.1.
If you are providing Eclipse Help in a .jar file (see §12.3.3 Configuring the Java manifest file for Eclipse Help), the default value (in fact the only valid value) of PluginSchemaVersion is 3.2. Do not set PluginSchemaVersion to 3.3, even if EclipseVer=3 (see §12.2.3 Deciding where to locate configuration settings).
If you are providing Eclipse Help in a .zip file, the value of PluginSchemaVersion can be either 3.0 or 3.1; the default value is 3.1.
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