Fortunately, I did find a solution to my problem. No need to answer my question anymore.

I'm having trouble with the additional calculator buttons for trigonometric and exponential/logarithmic functions. The trigonometric functions (sin, cos, tan, arcsin, arccos, arctan) and exponential/logarithmic functions (e^x, ln, log) aren't working correctly when I append their respective function strings to the input. I've included a minimal reproducible example in my question. Any guidance on integrating these buttons properly would be appreciated. Thanks!