Package structure

bootstrapui-<version>/
├── plugin/
│   ├── bootstrapui/
│   │   ├── plugin.min.js  ← the plugin for a plain <script> setup (required)
│   │   └── langs/         ← more languages, loaded by TinyMCE automatically
│   └── plugin.esm.js      ← the same plugin as an ES module for bundlers
├── documentation/
│   ├── index.html         ← this manual, readable offline
│   └── bootstrapui-manual.pdf  ← the same manual as PDF
├── example/tinymce-init.js   ← complete reference configuration
├── langs/bootstrapui.template.js  ← template for a new translation
├── LICENSE, NOTICE        ← licence and third-party notices
└── README.txt             ← installation, configuration and basic usage in brief

For a self-hosted TinyMCE copy the plugin/bootstrapui/ folder to tinymce/plugins/bootstrapui/. TinyMCE then finds the plugin by name. Anywhere else, load plugin.min.js with external_plugins: external_plugins: { bootstrapui: '/path/to/plugin.min.js' }.

TinyMCE and Bootstrap are not part of the package; you install both yourself.