When I click on any related entities, they do not appear for me, I get an error in console.

1. Open a more info dialog
2. Press settings cog in top right
3. Click "Related" tab
ha-related-items.ts:274 Uncaught (in promise) {code: "unknown_error", message: "Unknown error"}
value @ ha-related-items.ts:274
async function (async)
value @ ha-related-items.ts:272
value @ ha-related-items.ts:63
performUpdate @ updating-element.ts:720
_enqueueUpdate @ updating-element.ts:653
async function (async)
_enqueueUpdate @ updating-element.ts:640
_requestUpdate @ updating-element.ts:605
initialize @ updating-element.ts:449
initialize @ lit-element.ts:146
O @ updating-element.ts:438
V @ lit-element.ts:61
i @ subscribe-mixin.ts:13
i @ ha-related-items.ts:29
_clone @ template-instance.ts:99
__commitTemplateResult @ parts.ts:276
commit @ parts.ts:218
update @ template-instance.ts:53
__commitTemplateResult @ parts.ts:268
commit @ parts.ts:218
s @ render.ts:55
V.render @ shady-render.ts:277
update @ lit-element.ts:220
performUpdate @ updating-element.ts:704
_enqueueUpdate @ updating-element.ts:653
async function (async)
_enqueueUpdate @ updating-element.ts:640
_requestUpdate @ updating-element.ts:605
set @ updating-element.ts:313
value @ dialog-entity-registry-detail.ts:131
handleEvent @ parts.ts:505
__boundHandleEvent @ parts.ts:463
j @ property-effects.js:299
C @ property-effects.js:324
w @ property-effects.js:155
(anonymous) @ property-effects.js:242
_propertiesChanged @ property-effects.js:1657
_flushProperties @ properties-changed.js:352
_flushProperties @ property-effects.js:1502
_invalidateProperties @ property-effects.js:1474
_setProperty @ property-effects.js:1459
t.<computed> @ property-effects.js:2015
_selectionChange @ iron-multi-selectable.js:139
_applySelection @ iron-selectable.js:355
_applySelection @ iron-menu-behavior.js:274
setItemSelected @ iron-selection.js:77
select @ iron-selection.js:95
_selectSelected @ iron-selectable.js:292
_updateSelected @ iron-multi-selectable.js:102
I @ property-effects.js:811
w @ property-effects.js:155
v @ property-effects.js:121
_propertiesChanged @ property-effects.js:1654
_flushProperties @ properties-changed.js:352
_flushProperties @ property-effects.js:1502
_invalidateProperties @ property-effects.js:1474
_setProperty @ property-effects.js:1459
Object.defineProperty.set @ properties-changed.js:152
select @ iron-multi-selectable.js:66
select @ iron-menu-behavior.js:125
_itemActivate @ iron-selectable.js:395
_activateHandler @ iron-selectable.js:383
_activateHandler @ iron-menu-behavior.js:415
_activateHandler @ paper-tabs.js:407
(anonymous) @ template-stamp.js:87
M @ gestures.js:662
q @ gestures.js:1058
click @ gestures.js:1017
N @ gestures.js:450
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That's weird, it means you don't have the search integration loaded, which is marked as a dependency of the frontend and so should always be there. Are you sure you have pulled the latest beta?
I'm on 0.105.0b in Hass.io Home Assistant (not dev). I see all the other new stuff and have been playing with it but this doesn't appear to be working at all even after a restart.
Just noticed the new automations, scripts, and scenes cards that are under Device Info page also aren't functioning correctly. They all just say "no automations" even though I definitely have a bunch of existing ones in YAML and created a brand new one using the UI editor. I assume that uses the search integration also then.

I have the same issue
If you would like to test it before it is fixed, you can add this to your configuration.yaml:
search:
any errors in your backend log
It probably is a backend thing, I see:

I see the same error as @bramkragten after adding search: to my configuration
@SeanPM5 please also check the backend error logs next time 馃憤
Most helpful comment
It probably is a backend thing, I see:
