Title: Warning: Array to string conversion
Last modified: May 9, 2022

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# Warning: Array to string conversion

 *  Resolved [r0xta](https://wordpress.org/support/users/r0xta/)
 * (@r0xta)
 * [4 years ago](https://wordpress.org/support/topic/warning-array-to-string-conversion-2/)
 * As soon as I activate the plugin, I get this Warning on my website:
 * Warning: Array to string conversion in /var/www/web26346223/html/wp-content/plugins/
   hummingbird-performance/core/modules/minify/class-minify-group.php on line 959

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Support [Laura – WPMU DEV Support](https://wordpress.org/support/users/wpmudev-support8/)
 * (@wpmudev-support8)
 * [4 years ago](https://wordpress.org/support/topic/warning-array-to-string-conversion-2/#post-15627831)
 * Hi [@r0xta](https://wordpress.org/support/users/r0xta/)
 * I hope you’re well today and thank you for contacting us!
 * This is a warning only and shouldn’t affect site performance but of course it
   shouldn’t be there either.
 * It’s actually a bit “strange” that it happens – I checked the code around that
   line and all the variables used in it are (at least in theory) converted to arrays
   before this line is executed so it should prevent such warnings.
 * But it’s possible that there’s some “glitch” (in code or specific to the site).
 * Could you try temporarily disabling all cache on site/server and then resetting
   Asset Optimization in Hummingbird?
 * If it’s still happening after that, let me know, please:
 * – is Hummingbird on site up to date (version 3.3.2 currently)?
    – is WordPress
   itself and other plugins/theme up to date? – are you using any other JS/CSS optimization
   plugins on site at the same time (if yes, what are they)? – what PHP version 
   is powering your site?
 * Best regards,
    Adam
 *  Thread Starter [r0xta](https://wordpress.org/support/users/r0xta/)
 * (@r0xta)
 * [4 years ago](https://wordpress.org/support/topic/warning-array-to-string-conversion-2/#post-15628353)
 * Hey Adam, thanks for your help & time! Resetting Asset Optimization in Hummingbird
   seemed to do the trick.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘Warning: Array to string conversion’ is closed to new replies.

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 * 2 replies
 * 2 participants
 * Last reply from: [r0xta](https://wordpress.org/support/users/r0xta/)
 * Last activity: [4 years ago](https://wordpress.org/support/topic/warning-array-to-string-conversion-2/#post-15628353)
 * Status: resolved