Imaginary part of ${\rm Li}_2\left(\frac{1}{2}+ iq \right)$

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We all know that

$$\Re{ \left[{\rm Li}_{2}\left(\frac{1}{2}+iq\right) \right]}=\frac{{\pi}^{2}}{12}-\frac{1}{8}{\ln{\left(\frac{1+4q^2}{4}\right)}}^{2}-\frac{{\arctan^2{(2q)}}}{2}$$

where $q \in \mathbb{Q}$. How about the imaginary part of the equation? I have a feeling it involves beta Dirichlet function.

Addendum:

Sketch of proof:

Recall the fact that:

$${\rm Li}_2(\bar{z})=\overline{{\rm Li}_2(z)}$$

hence $$\Re{\rm Li}_2(z)=\frac{{\rm Li}_2(\bar{z}) + \overline{{\rm Li}_2(z)}}{2}$$

and then combine it with the very known functional equation

$${\rm Li}_2(z)+{\rm Li}_2(1-z)=\zeta(2)-\ln z \ln (1-z)$$

Thus the result. Maybe we can get the imaginary part by invoking the known relation:

$$\Im \left[ {\rm Li}_2 \right] =\frac{{\rm Li}_2(\bar{z}) - \overline{{\rm Li}_2(z)}}{2}$$