Examples of this could be that the fields load with delay, or once submitted the form lags before moving to a follow up page.
Isolate the cause
You can isolate the root of the lag by testing your form on a Marketo Landing Page
1. Locate the embedded form with in your instance
2. Build a landing page to test the form: Landing Page with a Form
3. Place your form on the new testing landing page, approve the page and close it.
4. Load the Landing Page using the URL
If the form loads with no delay, the issue lies with the embed code used to push the form onto the external page. Please work with your custom developer to find a resolution.
If the form is loading with a delay (and there is custom CSS):
1. Clone your form
2. Remove any custom CSS from with in the form
3. Build a landing page to test the form: Landing Page with a Form
4. Place your form on the new testing landing page, approve the page and close it.
5. Load the Landing Page using the URL
If you are not seeing any loading errors, the issue lies with in the custom CSS of your form. Please work with your custom coder to improve the loading speed of your form.
Note: Occasionally, incorporating the form embed script into containers (custom coding) and utilizing custom JavaScript may lead to delays in form functionality. In such instances, it is recommended to collaborate with your developer to identify a solution, as Marketo Support does not troubleshoot issues specifically related to custom coding.
If you are still seeing lag errors on your form loading on the Marketo Page, please submit a ticket with support@marketo.com