Is one who types something forbidden on a keyboard with Arabic letters, without looking at it, sinful?

It is not permissible to intentionally write or utter that which is unlawful, by any language or means, as Allah Almighty says: "And shun the word of falsehood" (22:30). As for unintentional, random writing that results in something unlawful, there is no sin in it as long as the heart did not intend it, as Allah Almighty says: "And there is no blame upon you for that in which you have erred, but [blame is due for] what your hearts intended" (33:5). This act is considered a frivolous deed that is not befitting of a rational person.