How do I write small っ

In the Write It sections, I'm having a hard time writing small っon the keyboard. How do I do this?

こんにちは Fred-さん! To write a small っ、you just have to double up on the letter that comes after it. For example, for something like って, you just write tte (see the extra t?) and it should do the trick. がんばって！

Thank you for the response! I should have made myself more clear, so I do apologize for my lack of precision. What I was referring to was the virtual keyboard found inside the web browser. This is located in the "Write It!" section of any lesson. From what you're telling me, yes I do agree, this will work on a Macintosh physical keyboard as I have done it myself many times. I was just curious about how to do it on the v1.49 keyboard in the "Write It!" section because the issue does elude me.

Hi Fred, Our apologies for any inconvenience. It's just come to our attention that the っ character is not included on the virtual keyboard. We'll get the IT team onto it. Thanks for letting us know!

Thank you for the prompt response. Please also note that the exclamation point is not available on the keyboard and some of the Write It! answers need an exclamation point.