You can use VBScript to do that,
Example for IE :
Create a file Switch.vbs with this :
Set WshShell = WScript.CreateObject("WScript.Shell")
WshShell.AppActivate "Internet Explorer"
Wscript.Sleep 1500
WshShell.SendKeys "^{TAB}"
Wscript.Sleep 1500
After opening your 2 tabs in IE run the command every 2 minutes :
wscript.exe switch.vbs
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