TL;DR If you're using v1.7.22 icons with Bootstrap, you'll want to update the helper CSS classes: https://materialdesignicons.com/bootstrap
For instance in the last release this syntax will now work. The documentation and
css on that page have been updated to also support this.
<button type="button" class="btn btn-default" aria-label="Flask"> <i class="mdi mdi-flask" aria-hidden="true"></i> btn </button> <!-- OR --> <button type="button" class="btn btn-default mdi mdi-flask" aria-label="Flask"> btn </button>
Hopefully this doesn't cause too much of a headache. Going forward it should be a beneficial change, but could be annoying for those upgrading
Preview the latest on the CDN: https://cdn.materialdesignicons.com/1.7.22/