Widget Page not loading and receiving errors in developer mode

Question

I'm getting the below errors, tried to following..

Using magento 2, php 7.2

Exception #0 (Exception): Warning: Magento\Framework\View\Element\Html\Calendar::_toHtml(): Cannot load resource element 'fields' in /home/sites/10a/0/0f56ee79d9/public_html/staging/vendor/magento/framework/View/Element/Html/Calendar.php on line 112

Exception #0 (Exception): Warning: Magento\Framework\View\Element\Html\Calendar::_toHtml(): Cannot load resource element 'fields' in /home/sites/10a/0/0f56ee79d9/public_html/staging/vendor/magento/framework/View/Element/Html/Calendar.php on line 112
<pre>#1 Magento\Framework\View\Element\Html\Calendar->_toHtml() called at [vendor/magento/framework/View/Element/AbstractBlock.php:1094]
#2 Magento\Framework\View\Element\AbstractBlock->Magento\Framework\View\Element\{closure}() called at [vendor/magento/framework/View/Element/AbstractBlock.php:1098]
#3 Magento\Framework\View\Element\AbstractBlock->_loadCache() called at [vendor/magento/framework/View/Element/AbstractBlock.php:671]
#4 Magento\Framework\View\Element\AbstractBlock->toHtml() called at [vendor/magento/framework/View/Layout.php:557]
#5 Magento\Framework\View\Layout->_renderBlock('head.calendar') called at [vendor/magento/framework/View/Layout.php:533]
#6 Magento\Framework\View\Layout->renderNonCachedElement('head.calendar') called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:206]
#7 Magento\Framework\View\Layout\Interceptor->renderNonCachedElement('head.calendar') called at [vendor/magento/framework/View/Layout.php:488]
#8 Magento\Framework\View\Layout->renderElement('head.calendar', false) called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:193]
#9 Magento\Framework\View\Layout\Interceptor->renderElement('head.calendar', false) called at [vendor/magento/framework/View/Layout.php:585]
#10 Magento\Framework\View\Layout->_renderContainer('after.body.start', false) called at [vendor/magento/framework/View/Layout.php:535]
#11 Magento\Framework\View\Layout->renderNonCachedElement('after.body.start') called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:206]
#12 Magento\Framework\View\Layout\Interceptor->renderNonCachedElement('after.body.start') called at [vendor/magento/framework/View/Layout.php:488]
#13 Magento\Framework\View\Layout->renderElement('after.body.start', false) called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:193]
#14 Magento\Framework\View\Layout\Interceptor->renderElement('after.body.start', false) called at [vendor/magento/framework/View/Layout.php:585]
#15 Magento\Framework\View\Layout->_renderContainer('backend.page', false) called at [vendor/magento/framework/View/Layout.php:535]
#16 Magento\Framework\View\Layout->renderNonCachedElement('backend.page') called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:206]
#17 Magento\Framework\View\Layout\Interceptor->renderNonCachedElement('backend.page') called at [vendor/magento/framework/View/Layout.php:488]
#18 Magento\Framework\View\Layout->renderElement('backend.page', false) called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:193]
#19 Magento\Framework\View\Layout\Interceptor->renderElement('backend.page', false) called at [vendor/magento/framework/View/Layout.php:585]
#20 Magento\Framework\View\Layout->_renderContainer('root', false) called at [vendor/magento/framework/View/Layout.php:535]
#21 Magento\Framework\View\Layout->renderNonCachedElement('root') called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:206]
#22 Magento\Framework\View\Layout\Interceptor->renderNonCachedElement('root') called at [vendor/magento/framework/View/Layout.php:488]
#23 Magento\Framework\View\Layout->renderElement('root', true) called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:193]
#24 Magento\Framework\View\Layout\Interceptor->renderElement('root') called at [vendor/magento/framework/View/Layout.php:954]
#25 Magento\Framework\View\Layout->getOutput() called at [generated/code/Magento/Framework/View/Layout/Interceptor.php:492]
#26 Magento\Framework\View\Layout\Interceptor->getOutput() called at [vendor/magento/framework/View/Result/Page.php:258]
#27 Magento\Framework\View\Result\Page->render(&Magento\Framework\App\Response\Http\Interceptor#000000001017c3ae000000000ff7c34a#) called at [vendor/magento/framework/View/Result/Layout.php:171]
#28 Magento\Framework\View\Result\Layout->renderResult(&Magento\Framework\App\Response\Http\Interceptor#000000001017c3ae000000000ff7c34a#) called at [generated/code/Magento/Backend/Model/View/Result/Page/Interceptor.php:193]
#29 Magento\Backend\Model\View\Result\Page\Interceptor->renderResult(&Magento\Framework\App\Response\Http\Interceptor#000000001017c3ae000000000ff7c34a#) called at [vendor/magento/framework/App/View.php:221]
#30 Magento\Framework\App\View->renderLayout() called at [vendor/magento/module-widget/Controller/Adminhtml/Widget/Instance/Index.php:22]
#31 Magento\Widget\Controller\Adminhtml\Widget\Instance\Index->execute() called at [generated/code/Magento/Widget/Controller/Adminhtml/Widget/Instance/Index/Interceptor.php:24]
#32 Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor->execute() called at [vendor/magento/framework/App/Action/Action.php:108]
#33 Magento\Framework\App\Action\Action->dispatch(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/module-backend/App/AbstractAction.php:231]
#34 Magento\Backend\App\AbstractAction->dispatch(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/framework/Interception/Interceptor.php:58]
#35 Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor->___callParent('dispatch', array(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#)) called at [vendor/magento/framework/Interception/Interceptor.php:138]
#36 Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor->Magento\Framework\Interception\{closure}(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/module-backend/App/Action/Plugin/Authentication.php:143]
#37 Magento\Backend\App\Action\Plugin\Authentication->aroundDispatch(&Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor#000000001017c0f7000000000ff7c34a#, &Closure#000000001017c0f6000000000ff7c34a#, &Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/framework/Interception/Interceptor.php:135]
#38 Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor->Magento\Framework\Interception\{closure}(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/framework/Interception/Interceptor.php:153]
#39 Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor->___callPlugins('dispatch', array(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#), NULL) called at [generated/code/Magento/Widget/Controller/Adminhtml/Widget/Instance/Index/Interceptor.php:39]
#40 Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor->dispatch(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/framework/App/FrontController.php:159]
#41 Magento\Framework\App\FrontController->processRequest(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#, &Magento\Widget\Controller\Adminhtml\Widget\Instance\Index\Interceptor#000000001017c0f7000000000ff7c34a#) called at [vendor/magento/framework/App/FrontController.php:99]
#42 Magento\Framework\App\FrontController->dispatch(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/framework/Interception/Interceptor.php:58]
#43 Magento\Framework\App\FrontController\Interceptor->___callParent('dispatch', array(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#)) called at [vendor/magento/framework/Interception/Interceptor.php:138]
#44 Magento\Framework\App\FrontController\Interceptor->Magento\Framework\Interception\{closure}(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/framework/Interception/Interceptor.php:153]
#45 Magento\Framework\App\FrontController\Interceptor->___callPlugins('dispatch', array(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#), array(array('default_store_se...', 'page_cache_from_...', 'storeCookieValid...', 'install', 'configHash'))) called at [generated/code/Magento/Framework/App/FrontController/Interceptor.php:26]
#46 Magento\Framework\App\FrontController\Interceptor->dispatch(&Magento\Framework\App\Request\Http#000000001017c3d5000000000ff7c34a#) called at [vendor/magento/framework/App/Http.php:137]
#47 Magento\Framework\App\Http->launch() called at [generated/code/Magento/Framework/App/Http/Interceptor.php:24]
#48 Magento\Framework\App\Http\Interceptor->launch() called at [vendor/magento/framework/App/Bootstrap.php:261]
#49 Magento\Framework\App\Bootstrap->run(&Magento\Framework\App\Http\Interceptor#000000001017c3a7000000000ff7c34a#) called at [index.php:39]

Tried running the following:

bin/magneto setup:upgrade

bin/magneto setup:di:compile

bin/magneto setup:static-content:deploy

also tried clearing cache and re indexing etc.

any help is appreciated.