IntraWeb uses Bootstrap 4 which is not fully backwards compatible with earlier Bootstrap versions. Many WordPress themes use Bootstrap and conflicts can occur which can cause undesired glitches in the theme if the theme uses an older version of Bootstrap.
This is in fact an issue with the main theme of our own website and why our documentation site uses a different theme than our main website.
When using IntraWeb content that uses Bootstrap controls the only current solution is to use a WordPress theme for those pages that does not use Bootstrap. If you cannot change the main theme, the Multiple Themes plugin can be of help.