Title: Uncaught SyntaxError: invalid regular expression flag
Last modified: January 16, 2023

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# Uncaught SyntaxError: invalid regular expression flag

 *  Resolved [milanbatinic](https://wordpress.org/support/users/milanbatinic/)
 * (@milanbatinic)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/)
 * Hi!
 * After update of Autoptimize to latest version i got this message on our companies
   website:
 * ‘Uncaught SyntaxError: invalid regular expression flag’
 * This results in video not being loaded on start page.
 * Do you have some idea how to solve this problem?
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Funcaught-syntaxerror-invalid-regular-expression-flag%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 10 replies - 1 through 10 (of 10 total)

 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377035)
 * Can you try adding `wp-content/plugins/facebook-conversion-pixel/` to the JS 
   optimization exclusion list?
 *  Thread Starter [milanbatinic](https://wordpress.org/support/users/milanbatinic/)
 * (@milanbatinic)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377231)
 * Hi!
 * Video plays after excluding facebook-conversion-pixel but that same error is 
   still showing in console plus one new error.
    -  This reply was modified 3 years, 4 months ago by [milanbatinic](https://wordpress.org/support/users/milanbatinic/).
    -  This reply was modified 3 years, 4 months ago by [milanbatinic](https://wordpress.org/support/users/milanbatinic/).
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377528)
 * OK, can you disable the “Minify excluded CSS and JS files?” option (main settings
   page near the bottom)?
 *  Thread Starter [milanbatinic](https://wordpress.org/support/users/milanbatinic/)
 * (@milanbatinic)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377686)
 * This one is left ‘Uncaught TypeError: r is undefined’
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377739)
 * not sure how much of a problem this is, but maybe try switching your JS configuration
   to the now default “don’t aggregate but defer” + “also defer inline JS”, removing
   the exclusions you currently have to start with?
 *  Thread Starter [milanbatinic](https://wordpress.org/support/users/milanbatinic/)
 * (@milanbatinic)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377884)
 * Would it help if i turn of facebook pixel plugin?
 *  Thread Starter [milanbatinic](https://wordpress.org/support/users/milanbatinic/)
 * (@milanbatinic)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377909)
 * Error ‘Uncaught TypeError: r is undefined’ is still there even when i turn off
   plugin
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16377999)
 * ah, in that case it’s not related/ due to AO to begin with, so you could keep
   the config as is?
 *  Thread Starter [milanbatinic](https://wordpress.org/support/users/milanbatinic/)
 * (@milanbatinic)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16378107)
 * I’ve set config as it was when we started. Thank you for all the answers and 
   help. I will leave it with this error ‘Uncaught TypeError: r is undefined’ for
   now.
 * Regards
 * Milan
 *  Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * (@optimizingmatters)
 * [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16378114)
 * You’re welcome Milan, feel free to [leave a review of the plugin and support here](https://wordpress.org/support/plugin/autoptimize/reviews/#new-post)!
   🙂

Viewing 10 replies - 1 through 10 (of 10 total)

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 * 10 replies
 * 2 participants
 * Last reply from: [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/)
 * Last activity: [3 years, 4 months ago](https://wordpress.org/support/topic/uncaught-syntaxerror-invalid-regular-expression-flag/#post-16378114)
 * Status: resolved