dataLogTimer is not defined

short description

After each Update when clicking on i.e. Websites > Subdomains the Spinner comes up and nothing happens The error in the Console:

Uncaught ReferenceError: dataLogTimer is not defined
    at Object.success (ispconfig.js:290)
    at j (jquery.min.js:2)
    at Object.fireWith [as resolveWith] (jquery.min.js:2)
    at x (jquery.min.js:4)
    at XMLHttpRequest.<anonymous> (jquery.min.js:4)

correct behaviour

The List of Subdomains should be visible

environment

Server OS: Ubuntu Server OS version: 16.10, 18.04 ISPConfig version: 3.1.13

proposed fix

Like all other Variables, in ./interface/web/themes/default/assets/javascripts/ispconfig.js replace the two

• clearTimeout(dataLogTimer);

with

• clearTimeout(ISPConfig.dataLogTimer);