Important Notes

To increase the memory.
To increase the memory in magento. If you are getting error of memory or time limit. Write the below line in that file.

ini_set('memory_limit', -1);

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Facebook connect by belvg
In facebook connect plugin, there is an error, after i run the setup:upgrade.

The solution i got from somewhere is that add below code in system.xml file.
<tab id="belvg">
            <label>Vendor Name</label>
</tab>

The result will be like this.
<system>
        <tab id="belvg">
            <label>Vendor Name</label>
        </tab>
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