Structure of the Jacobson radical of the Group Algebra .

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Is it possible to find the structure description of the Jacobson radical $J(FG)$ of a group algebra FG, where F and G are finite field and group respectively in GAP?

I choose the group algebra $F_3D_{30}$, where $F$ is a finite field of characteristic $3$ and $D_{30}$ is the dihedral group of order $30.$ Actually I need the algebraic structure of $1+J(F_3D_{30})$ as it is a subgroup of the unit group $U(F_3D_{30})$, so I am thinking first the structure of $J(F_3D_{30})$. I tried as

gap> RadicalOfAlgebra(GroupRing(GF(3),D30));

<algebra of dimension 20 over GF(3)>

gap> H:=RadicalOfAlgebra(GroupRing(GF(3),D30));;

gap> Size(H);

3486784401

gap> IsAbelian(H);

false

gap> Center(H);

<algebra of dimension 10 over GF(3)>

brk_3> StructureDescription(H);

Error, no method found!

StructureDescription is not working. Is there any way to find its algebraic structure using GAP? Please help. Thank you.