Improve installer's internal checks or add "Continue anyway" button
Currently, it's impossible to install FirefoxPortable while an instance of FirefoxPortable is already running, due to this alert:
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Mozilla Firefox, Portable Edition | PortableApps.com Installer
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Please close all instances of Mozilla Firefox, Portable Edition and then click OK. The portable app can not be upgraded while it is running.
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ОК Cancel
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