PHP 7 compatibility

Hi,

I am using Storefront. I did a test with the Plugin PHP compatibility what was the problem when upgrading to php7 and this is what I’ve got as a result:

FILE: /home…/MySite/public_html/wp-content/plugins/so-widgets-bundle/base/inc/lib/Less/Parser.php
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FOUND 0 ERRORS AND 3 WARNINGS AFFECTING 3 LINES
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93 | WARNING | INI directive ‘mbstring.internal_encoding’ is deprecated since PHP 5.6
94 | WARNING | INI directive ‘mbstring.internal_encoding’ is deprecated since PHP 5.6
229 | WARNING | INI directive ‘mbstring.internal_encoding’ is deprecated since PHP 5.6
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FILE: /home…/MySite/public_html/wp-content/plugins/so-widgets-bundle/base/inc/lib/Less/SourceMap/Base64VLQ.php
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FOUND 3 ERRORS AFFECTING 1 LINE
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156 | ERROR | Bitwise shifts by negative number will throw an ArithmeticError in PHP 7.0
156 | ERROR | Bitwise shifts by negative number will throw an ArithmeticError in PHP 7.0
156 | ERROR | Bitwise shifts by negative number will throw an ArithmeticError in PHP 7.0
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What do you think I should do?

Greetings,