Some useful tips & tricks that make working with the web view easier.
1.) Use an external HTML file. Best solution is to place it in the preset's data folder and reference it using BTT_PRESET_PATH/thenameofthefile.html. You can use your facorite editor (I recommend Visual Studio Code) to edit the file. .
2.) Disable caching while developing. You probably want the webview to automatically reload when hiding / closing it. To achieve this, enable the "DO NOT keep active in background" option. .
3.) Use the debugger / inspector. You can right-click any BTT webview and choose "Inspect Element" to open the webview inspector. This can be a bit slow though. If you want faster debugging enable Safari's developer mode, then you can also access the BTT webviews through the Safari Develop menu: