protected List<ResourceFile> findExtensionInstallationDirectories() {

		List<ResourceFile> dirs = new ArrayList<>();
		dirs.add(new ResourceFile(new File(userSettingsDir, "Extensions")));

		if (SystemUtilities.isInDevelopmentMode()) {
			ResourceFile rootDir = getApplicationRootDirs().iterator().next();
			File temp = new File(rootDir.getFile(false), "Extensions");
			if (temp.exists()) {
				dirs.add(new ResourceFile(temp)); // ghidra/Ghidra/Extensions
			}
		}
		else {
			dirs.add(new ResourceFile(applicationInstallationDir, "Ghidra/Extensions"));
		}

		return dirs;
	}
Returns a prioritized list of directories where Ghidra extensions are installed. These
should be at the following locations:<br>
<ul>
<li><code>[user settings dir]/Extensions</code></li>
<li><code>[application install dir]/Ghidra/Extensions</code> (Release Mode)</li>
<li><code>ghidra/Ghidra/Extensions</code> (Development Mode)</li>
</ul>

@return the install folder, or null if can't be determined
Ghidra/Framework/Utility/src/main/java/ghidra/GhidraApplicationLayout.java