Applying plain implications fails
Here's two testcases, both fail currently:
Lemma test_apply_affine_wand2 `{!BiPlainly PROP} (P : PROP) :
P -∗ (∀ Q : PROP, <affine> ■ (Q -∗ <pers> Q) -∗ <affine> ■ (P -∗ Q) -∗ Q).
Proof. iIntros "HP" (Q) "_ HPQ". by iApply "HPQ". Qed.
Lemma test_apply_affine_impl2 `{!BiPlainly PROP} (P : PROP) :
P -∗ (∀ Q : PROP, ■ (Q -∗ <pers> Q) → ■ (P -∗ Q) → Q).
Proof. iIntros "HP" (Q) "_ HPQ". by iApply "HPQ". Qed.