Why Does My JavaScript Only Work in Internet Explorer After Opening Developer Tools?

JavaScript Functioning Enigma in Internet Explorer

Users report an inexplicable behavior in Internet Explorer, where JavaScript functionalities remain dormant until the developer tools are opened once. This anomaly manifests in an example provided by the user, highlighting a "Download PDF" feature that fails to function in IE despite working flawlessly in other browsers.

To their astonishment, the puzzling behavior abruptly transforms when the developer toolbar is toggled using the F12 key. This seemingly insignificant action magically unlocks the JavaScript's ability to function as intended.

Decoding the Discrepancy

The user's frustration stems from a common misconception regarding debugging code in JavaScript. The appearance of console.log() or other console functionalities within the code can often lead to this peculiar behavior in IE.

In Internet Explorer, the console object remains inert until the developer toolbar is opened. Attempting to invoke console-related functions prior to this action results in an undefined error. Once the toolbar is opened, the console object becomes available, enabling subsequent console calls to execute successfully, even after the toolbar is closed.

Resolving the Issue

Three solutions can effectively address this inconvenience:

1. Eliminate Console References: Remove all occurrences of console references in the production code.
2. Conditional Execution: Wrap console references within an if() statement or a conditional check that verifies the existence of the console object before invoking it.
3. Explorer-Conditional Code: Include Explorer-specific code that conditionally invokes console functions only when the browser is detected to be IE.

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