This article will help you to solve the widget error which says “Cannot read properties of undefined (reading ‘map’)” in WordPress by following some steps.

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Fix this error “Cannot read properties of undefined (reading map)”
The vexing widget error message “Cannot read properties of undefined (reading map)” in WordPress often arises when attempting to access an array or object that is nonexistent or null. The consequences of this error can be exceptionally frustrating, and the operation of your website may suffer as a result.
Here are a few strategies to resolve this issue:
Here is a simple trick to solve widget errors in WordPress. You can solve this by following a few steps:
- First, check the code: If this error occurs in your WordPress theme or plugin code, check the code to determine if you’re trying to access an undefined variable or object. Make sure the variable or object exists before attempting to access its properties.
- Secondly, disable plugins: It’s plausible that a plugin conflict could be the root cause of this error. To assess whether this is the case, deactivate all plugins on your website and observe if the error persists. If the error disappears, re-activate each plugin one by one until you pinpoint the cause of the conflict.
- Third, switch to the default theme: If the error persists despite disabling all plugins, swap to the default WordPress theme (such as Twenty Twenty-One) to check whether the error disappears. If it does, then the error is probably related to your theme.
- Fourth, update WordPress: Make sure you have installed the most up-to-date version of WordPress as older versions can sometimes result in errors.
- Finally, verify for syntax errors: Make sure that your code does not contain syntax errors as these can also contribute to this error. You can use a code editor or online tool to inspect your code for syntax errors.
By adhering to these measures, you should be able to resolve the “Cannot read properties of undefined (reading ‘map’)” error in WordPress.