Changes

// suppress console.log, switch to true for debug

// suppress console.log, switch to true for debug

var Debug_switch = true;

var Debug_switch = false;

// seemingly the Safari engine uses a somewhat different implementation of arguments for db.transaction and index.get

// seemingly the Safari engine uses a somewhat different implementation of arguments for db.transaction and index.get

// because no browser on any mac / ios is allowed to use a different engine, rather than user agent, platform can be tested

// because no browser on any mac / ios is allowed to use a different engine, rather than user agent, platform can be tested