Test various text attributes: parse, MathJax, JessieCode, value-tag

1234−1−2−3−41234−1−2−3−4
A
Hallo Welt
x2
valx X(A)+1+π=6.14
2X(A)+π=7.14
√valx 1+1+π=5.14
2.000+π

JessieCode tag

html tags should be ignored.
Hallo <span class="my">Welt</span>