@Test
	public void testDeletePlates() throws Exception {
		Listing listing = program.getListing();
		ArrayList<Address> list = new ArrayList<>();
		FunctionIterator iter = program.getFunctionManager().getFunctions(true);
		while (iter.hasNext()) {
			Function f = iter.next();
			String[] comments = f.getCommentAsArray();
			if (comments != null && comments.length == 1 && comments[0].equals(" FUNCTION")) {
				list.add(f.getEntryPoint());
			}
		}
		ScriptTaskListener scriptID = env.runScript(script);
		assertNotNull(scriptID);

		waitForScriptCompletion(scriptID, 1200000);

		program.flushEvents();
		waitForSwing();

		for (int i = 0; i < list.size(); i++) {
			Address addr = list.get(i);
			Function f = listing.getFunctionAt(addr);
			assertNull(f.getComment());
		}
	}
Test for deleting default plate comments on a function
Ghidra/Features/Base/src/test.slow/java/ghidra/app/plugin/core/script/DeleteFunctionDefaultPlatesScriptTest.java