Ghost/ghost/admin/app/components/custom-theme-settings/image.hbs

<div class="gh-stack-item {{if (eq @index 0) "gh-setting-first" "gh-setting"}}">
    <GhUploader
        @extensions={{this.imageExtensions}}
        @onComplete={{this.imageUploaded}}
        as |uploader|
    >
        <div class="{{if @setting.value "" "flex flex-grow-1 items-center justify-between"}}">
            <div class="gh-setting-content">
                <div class="gh-setting-title {{if @setting.value "gh-theme-setting-title"}}">{{humanize-setting-key @setting.key}}</div>
                {{#each uploader.errors as |error|}}
                    <div class="gh-setting-error" data-test-error="icon">{{or error.context error.message}}</div>
                {{/each}}
            </div>
            <div class="gh-setting-action gh-uploadbutton-container flex flex-column items-stretch">
                {{#if uploader.isUploading}}
                    {{uploader.progressBar}}
                {{else if @setting.value}}
                    <div class="gh-branding-image-container largeimg justify-start">
                        <img class="blog-cover" src={{@setting.value}} {{on "click" uploader.triggerFileDialog}}>
                        <button type="button" class="gh-setting-action-largeimg-delete" {{on "click" (fn this.updateValue null)}} data-test-delete-image="icon">
                            {{svg-jar "trash" class="w4 h4 fill-white"}}
                        </button>
                    </div>
                {{else}}
                    <button type="button" class="gh-btn gh-btn-white self-start" {{on "click" uploader.triggerFileDialog}} data-test-image-upload-btn="icon">
                        <span>Upload</span>
                    </button>
                {{/if}}
                <div style="display:none">
                    <GhFileInput @multiple={{false}} @action={{uploader.setFiles}} @accept={{this.imageMimeTypes}} @onInsert={{uploader.registerFileInput}} data-test-file-input="icon" />
                </div>
            </div>
        </div>
    </GhUploader>
</div>