Conflict with the Simple Custom CSS and JS plugin

The WP Page Widget plugin loads the Page Widgets metabox only on the selected post types, but it still loads the JS files necessary for the metabox on all the post types. This leads to a JS error on the Simple Custom CSS and JS plugin.

Would it be possible to load the JS files only for the selected post types? There are only two lines of codes to perform such a check.

Here is a screenshot of the code with the changes. Or here is a diff of the code changes.