PROOF THAT IT WORKS:
https://i.imgur.com/j9IKT62.gifv
NOTES:
01.) I didn't want to use 'PortableApps.com' to pin my 'Firefox Portable' browser for various reasons, one being that it did not work for me. Scroll down to the very bottom for more information.
02.) The following method will also work with all other portable browsers and portable apps.
03.) For my instructions, I will be using 'Mozilla Firefox, Portable Edition' as an example.
CREDITS:
RaMMicHaeL, the developer of '7+ Taskbar Tweaker'. He is the one who told me about the 'Win7AppID' tool, and it is his '7+ Taskbar Tweaker' program that I used to get my portable app's AppID.
STEP #01 - DOWNLOAD A PROGRAM THAT WILL TELL YOU YOUR PORTABLE APP'S APPID.
01.) https://rammichael.com/7-taskbar-tweaker
02.) Download and install the latest version of '7+ Taskbar Tweaker'.
03.) Open up 'Mozilla Firefox, Portable Edition'.
04.) Run '7+ Taskbar Tweaker'.
05.) Click on the '7+ Taskbar Tweaker' icon that is in your System Tray.
06.) On the bottom right corner of the '7+ Taskbar Tweaker' window, click the 'Taskbar Inspector' button.
07.) Screenshot the popup 'Taskbar Inspector' window. You will need to screenshot it because the window disappears once you click outside of the window.
08.) Open up the screenshot that you just took. Look for the website that you have open in 'Mozilla Firefox, Portable Edition'. One line above that is the AppID for 'Mozilla Firefox, Portable Edition'. Write it down. My AppID number was 2B22C18D2D4725BA. Your AppID will be different than mine, even if you are using the same portable browser.
STEP #02 - DOWNLOAD A DUMMY EXE. WE WILL ONLY BE USING THIS TEMPORARILY.
01.) https://sourceforge.net/projects/exeresource/files/latest/download
NOTE: We are using this particular dummy exe for several reasons. If you were to use a program that is already on your computer like 'Microsoft Edge' and you changed the shortcut's target path and icon, it will be very hard to change them back later. If you were to use let's say another portable app's .exe, you won't be able to pin the .exe's shortcut to the taskbar because it as a portable app. This dummy exe that we will be using is very small in size, we won't ever need to run it, and even if we did run it by accident it will do nothing. It is a portable .exe so there won't be additional files or folders anywhere else. And will be deleting it when we are done.
02.) Download 'Simple EXE Resource'. It will actually save as a 'existential.zip' folder. It doesn't matter where you save it, as long as you remember the location.
03.) Extract the 'existential.zip' folder. The folder's name will be 'existential'.
04.) Rename the 'existential' folder to 'Firefox Portable (new)'.
05.) Delete the 'existential.bas' and 'WTFPLv3.txt' files inside the folder. We only need 'existential.exe'.
06.) Right click the 'existential.exe' file and select 'Create Shortcut'. You want the shortcut to be in the same folder, not on the Desktop.
07.) Rename the shortcut that you just created to '01'.
STEP #03 - DOWNLOAD THE PROGRAM THAT YOU WILL NEED TO CHANGE A SHORTCUT'S APPID.
01.) https://code.google.com/archive/p/win7appid/downloads
02.) Download the Jan 27, 2010 program called 'Win7AppID.exe'
03.) Move this 'Win7AppID.exe' into the 'Firefox Portable (new)' folder.
STEP #04 - CREATE A NEW SHORTCUT WITH THE DESIRED APPID AND TARGET PATH.
01.) Pin the '01.lnk' that is inside the 'Firefox Portable (new)' folder to the Taskbar. IMPORTANT: You must pin it to the Taskbar first before doing anything else like changing the target path. And don't bother running it. We will only run it once we have changed the AppID and target path.
02.) Open up the 'Firefox Portable (new)' folder, and click inside the rectangle box at the top of the File Explorer window. This will highlight everything. Type 'cmd' without the single quotation marks, and press the Enter key. This will create a Command Prompt window for your 'Firefox Portable (new)' folder.
03.) Inside the Command Prompt window, type the following and press Enter:
Win7AppId 01.lnk 2B22C18D2D4725BA
NOTE: 2B22C18D2D4725BA is the AppID of my 'Mozilla Firefox, Portable Edition' app. Your AppID will be different, so use the AppID that you obtained in Step #01.
04.) Go to the folder where you have 'Mozilla Firefox, Portable Edition' installed. Right click the 'FirefoxPortable.exe' and select 'Create Shortcut'.
05.) Right click the shortcut that you just created and select 'Cut'.
06.) Go back to the 'Firefox Portable (new)' folder and paste the 'FirefoxPortable.lnk' shortcut in it.
07.) Right click the '01.lnk' shortcut and select 'Properties'. Right click the 'FirefoxPortable.lnk' shortcut and select 'Properties'.
08.) Now replace the 'Target:' path in '01.lnk' with the 'Target:' path that is in 'FirefoxPortable.lnk'. And do the same for 'Start in:'. Click 'Apply' to save the changes.
09.) The '01.lnk' that you have pinned to the Taskbar should now open up 'Mozilla Firefox, Portable Edition' exactly where your pinned icon is, and it should no longer create duplicate icons. We will soon be renaming the pinned '01.lnk' to a better name in the next step.
STEP #05 - DELETE EVERYTHING THAT YOU DOWNLOADED, RENAME THE PINNED SHORTCUT, AND MAKE A BACKUP OF THE PINNED SHORTCUT.
01.) Go ahead and delete everything that you have downloaded so far. You can delete 'existential.zip', the 'existential' folder that we renamed to 'Firefox Portable (new)', and the 'Win7AppID.exe'. If there was anything else that we downloaded or created, go ahead and delete it. So basically your system will be exactly as it was before.
02.) Go to "C:\Users\YOURUSERNAME\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar". This will have all the shortcuts to the programs that you currently have pinned to the Taskbar.
03.) Locate '01' and rename it to something better. I renamed mine 'Firefox Portable'.
04.) Right click the 'Firefox Portable.lnk" inside the aforementioned "...\User Pinned\TaskBar" folder and select 'Copy'. Then 'Paste' a copy of it in a different, secure location. Why? If you accidently click 'Unpin from Taskbar' one day, this shortcut that you spent so much time creating will have completely and permanently disappeared. Then what? If you have a backup of it, you just put a copy of it back in the "...\User Pinned\TaskBar" folder, which will save you a lot of time and headache.
WHY I DIDN'T USE PORTABLEAPPS.COM?
Someone suggested that I use 'PortableApps.com' to pin portable apps to the Taskbar. I had already tried that with 'Mozilla Firefox, Portable Edition' and it did not work. I installed the latest version of 'PortableApps.com'. Then I installed a new copy of 'Mozilla Firefox, Portable Edition' using 'PortableApps.com'. Then inside the 'PortableApps.com' program window, I right clicked the 'Firefox Portable' entry and selected 'Pin to Taskbar'. 'PortableApps.com' then opened up a new File Explorer window with a 'Firefox Portable' shortcut in it, and it instructed me to drag this shortcut to the Taskbar to pin it. It would not let me pin it to the Taskbar -> there was a red circle with a diagonal line across it. Furthermore, I don't want to have or use 'PortableApps.com'. I like having my "Firefox Portable' in a parent folder instead of a child folder of some other program, and I don't need 'PortableApps.com' for anything else as 'Firefox Portable' is the only app that I use and it auto updates itself. So 'PortableApps.com' just takes up USB drive space and makes things more complicated, and it didn't even work for me. Some people might be happy using the 'PortableApps.com' method. I am not one of those people. So I had to come up with a different method, and many thanks to RaMMicHaeL for helping me find that working method.