signal refs are sometimes not set to null when they should be

[ged-odoo]

import { Component, mount, xml, signal } from "@odoo/owl";

class Root extends Component {
    static template = xml`<div>
        Hello Owl!
        <t t-out="!!this.s()"/>
        <div t-if="this.isVisible()">
            <div t-if="true">
                <span t-ref="this.s">asdf</span>
            </div>
        </div>
    </div>`;

    s = signal.ref();
    isVisible = signal(true);

    setup() {
        setInterval(() => {
            this.isVisible.set(!this.isVisible())
        }, 2000)
    }
}

mount(Root, document.body, { templates: TEMPLATES, dev: true });

and this one:

import { Component, mount, xml, signal } from "@odoo/owl";
import { Dialog } from "./dialog";


class Wrapper extends Component {
    static template = xml`<div t-if="this.isVisible()"><t t-call-slot="default"/></div>`
    isVisible = signal(true);
    setup() {
        setInterval(() => {
            this.isVisible.set(!this.isVisible());
        }, 2000)
    }
}

class Root extends Component {
    static components = { Wrapper };
    static template = xml`
        <button t-on-click="() => this.toggle()">Show</button>
        <div><t t-out="this.isRefActif()"/> </div>
        <t t-if="this.isVisible()">
          <Wrapper title="'Hello'" onClose="() => this.toggle(false)">
            <div t-debug="" t-ref="this.myRef">Coucou</div>
          </Wrapper>
        </t>`;

    isVisible = signal(false);
    myRef = signal.ref();

    toggle(visible) {
        this.isVisible.set(!this.isVisible());
    }

    isRefActif() {
        return this.myRef() !== null;
    }
}

mount(Root, document.body, { templates: TEMPLATES, dev: true });