array(7) {
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    ["line"] => int(48)
    ["function"] => string(23) "createRootDirIfNotExist"
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    ["args"] => array(0) {
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    ["file"] => string(62) "/srv/twist-track/vendor/wurfl/wurfl-api/WURFL/Storage/File.php"
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    ["function"] => string(10) "initialize"
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    ["function"] => string(11) "__construct"
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        ["configurationFileDir":protected] => NULL
        ["allowReload":protected] => bool(true)
        ["wurflFile":protected] => string(98) "/srv/twist-track/legacy/library/Track/../../../vendor/wurfl/wurfl-api/examples/resources/wurfl.zip"
        ["wurflPatches":protected] => NULL
        ["capabilityFilter":protected] => array(2) {
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          [1] => string(9) "is_tablet"
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        ["logDir":protected] => NULL
        ["matchMode":protected] => string(11) "performance"
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}
The file storage directory is not writeable: /srv/twist-track/legacy/library/Track/../../../cache/wurfl/persistence