jellyfin-web/dashboard-ui/librarypathmapping.html

<div id="libraryPathMappingPage" data-role="page" class="page type-interior librarySectionPage" data-helpurl="https://github.com/MediaBrowser/Wiki/wiki/Library%20setup" data-require="scripts/librarypathmapping">

    <div data-role="content">
        <div class="content-primary">
            <div data-role="controlgroup" data-type="horizontal" class="localnav" data-mini="true">
                <a href="library.html" data-role="button">${TabFolders}</a>
                <a href="#" data-role="button" class="ui-btn-active">${TabPathSubstitution}</a>
                <a href="librarysettings.html" data-role="button">${TabAdvanced}</a>
            </div>

            <div class="readOnlyContent">
                <p>${PathSubstitutionHelp}</p>

                <div class="pathSubstitutions"></div>
            </div>

            <br />

            <form class="libraryPathMappingForm">

                <div>
                    <h3 class="detailSectionHeader">${ButtonAddPathSubstitution}</h3>
                    <div>
                        <label for="txtFrom">${LabelFrom}</label>
                        <input id="txtFrom" type="text" required="required" data-mini="true" />
                        <div class="fieldDescription labelFromHelp"></div>
                    </div>
                    <br />
                    <div>
                        <label for="txtTo">${LabelTo}</label>
                        <input id="txtTo" type="text" required="required" data-mini="true" />
                        <div class="fieldDescription">${LabelToHelp}</div>
                    </div>
                    <br />
                    <button type="submit" data-role="none" class="clearButton">
                        <paper-button raised class="submit block"><iron-icon icon="add"></iron-icon><span>${ButtonAdd}</span></paper-button>
                    </button>
                </div>

            </form>

        </div>
    </div>
</div>