psdbComponent.clickDocumentLink();
ArrayList<String> tabs2 = new ArrayList<String> (driver.getWindowHandles());
driver.switchTo().window(tabs2.get(1));
driver.close();
driver.switchTo().window(tabs2.get(0));
This code perfectly worked for me. Try it out. You always need to switch your driver to a new tab, before you want to do something on a new tab.
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Thanks!