} catch (ConfigPropertyNotFoundException e) {
            assertEquals("non.existent.property", e.getMessage());
        }
    }

    // Test isExtensionAllowed method
    /*
    // Commented out - methods don't exist in FessConfig
    @Test
    public void test_isExtensionAllowed() {
        assertTrue(fessConfig.isExtensionAllowed("jpg"));
        assertTrue(fessConfig.isExtensionAllowed("jpeg"));

        }

        @Override
        public void flushBuffer() {
        }

        @Override
        public void resetBuffer() {
        }

        @Override
        public boolean isCommitted() {
            return false;
        }

        @Override
        public void reset() {
        }

        @Override
        public void setLocale(java.util.Locale loc) {
        }

        @Override
        public void flushBuffer() {
        }

        @Override
        public void resetBuffer() {
        }

        @Override
        public boolean isCommitted() {
            return false;
        }

        @Override
        public void reset() {
        }

        @Override
        public void setLocale(java.util.Locale loc) {
        }

        final String content = msg.getContent();
        if (content == null) {
            return null;
        }
        final String omitMarker = "\n...[omitted]...\n";
        final int maxSuffixLen = Math.max(0, maxChars / 4);
        final String suffix = buildSourceTitlesSuffix(msg.getSources(), maxSuffixLen);