foundry/Data/systems/pf2e/templates/items/affliction-sidebar.hbs

<div class="inventory-details">
    <div class="form-group">
        <label>{{localize "PF2E.Item.Affliction.OnsetLabel"}}</label>
        {{#if data.onset}}
            {{> systems/pf2e/templates/items/partials/duration.hbs base="system.onset" duration=data.onset units=onsetUnits}}
            <div class="item-controls">
                <a data-action="onset-delete"><i class="fas fa-fw fa-times"></i></a>
            </div>
        {{else}}
            <div class="form-fields">
                <button type="button" data-action="onset-add"><i class="fas fa-plus"></i>Add Onset</button>
            </div>
        {{/if}}
    </div>
    <div class="form-group">
        <label>{{localize "PF2E.Time.Duration"}}</label>
        {{> systems/pf2e/templates/items/partials/duration.hbs base="system.duration" duration=data.duration units=durationUnits}}
    </div>

    {{#if user.isGM}}
        <div class="form-group">
            <label for="data.unidentified">{{localize "PF2E.Item.Effect.Unidentified"}}</label>
            <div class="form-fields">
                <input type="checkbox" name="system.unidentified" {{checked data.unidentified}} />
            </div>
        </div>
    {{/if}}

    <hr/>

    <div class="form-group">
        <label>{{localize "PF2E.Item.Affliction.StageLabel"}}</label>
        <select name="system.stage" data-dtype="Number" {{disabled (not item.actor)}}>
            {{#select item.stage}}
                {{#if item.onsetDuration}}
                    <option value="0">{{localize "PF2E.Item.Affliction.OnsetLabel"}}</option>
                {{/if}}
                {{#times item.maxStage as |idx|}}
                    <option value="{{add idx 1}}">{{localize "PF2E.Item.Affliction.Stage" stage=(add idx 1)}}</option>
                {{/times}}
            {{/select}}
        </select>
    </div>

</div>