diff --git a/src/login/UserProfileFormFields.tsx b/src/login/UserProfileFormFields.tsx
index f9edefb9..4d883b76 100644
--- a/src/login/UserProfileFormFields.tsx
+++ b/src/login/UserProfileFormFields.tsx
@@ -1,8 +1,7 @@
 import { useEffect, Fragment } from "react";
 import type { ClassKey } from "keycloakify/login/TemplateProps";
-import { clsx } from "keycloakify/tools/clsx";
 import { useUserProfileForm, type KcContextLike, type FormAction, type FormFieldError } from "keycloakify/login/lib/useUserProfileForm";
-import type { Attribute, LegacyAttribute } from "keycloakify/login/kcContext/KcContext";
+import type { Attribute } from "keycloakify/login/kcContext/KcContext";
 import { assert } from "tsafe/assert";
 import type { I18n } from "./i18n";
 
@@ -49,20 +48,9 @@ export default function UserProfileFormFields(props: UserProfileFormFieldsProps)
     return (
         <>
             {formFieldStates.map(({ attribute, displayableErrors, valueOrValues }) => {
-                const formGroupClassName = clsx(
-                    getClassName("kcFormGroupClass"),
-                    displayableErrors.length !== 0 && getClassName("kcFormGroupErrorClass")
-                );
-
                 return (
                     <Fragment key={attribute.name}>
-                        <GroupLabel
-                            attribute={attribute}
-                            getClassName={getClassName}
-                            i18n={i18n}
-                            groupNameRef={groupNameRef}
-                            formGroupClassName={formGroupClassName}
-                        />
+                        <GroupLabel attribute={attribute} getClassName={getClassName} i18n={i18n} groupNameRef={groupNameRef} />
                         {BeforeField !== undefined && (
                             <BeforeField
                                 attribute={attribute}
@@ -73,7 +61,7 @@ export default function UserProfileFormFields(props: UserProfileFormFieldsProps)
                             />
                         )}
                         <div
-                            className={formGroupClassName}
+                            className={getClassName("kcFormGroupClass")}
                             style={{ "display": attribute.name === "password-confirm" && !doMakeUserConfirmPassword ? "none" : undefined }}
                         >
                             <div className={getClassName("kcLabelWrapperClass")}>
@@ -142,41 +130,11 @@ function GroupLabel(props: {
     groupNameRef: {
         current: string;
     };
-    formGroupClassName: string;
 }) {
-    const { attribute, getClassName, i18n, groupNameRef, formGroupClassName } = props;
+    const { attribute, getClassName, i18n, groupNameRef } = props;
 
     const { advancedMsg } = i18n;
 
-    keycloak_prior_to_24: {
-        if (attribute.html5DataAnnotations !== undefined) {
-            break keycloak_prior_to_24;
-        }
-
-        const { group = "", groupDisplayHeader = "", groupDisplayDescription = "" } = attribute as any as LegacyAttribute;
-
-        return (
-            <>
-                {group !== groupNameRef.current && (groupNameRef.current = group) !== "" && (
-                    <div className={formGroupClassName}>
-                        <div className={getClassName("kcContentWrapperClass")}>
-                            <label id={`header-${group}`} className={getClassName("kcFormGroupHeader")}>
-                                {advancedMsg(groupDisplayHeader) || groupNameRef.current}
-                            </label>
-                        </div>
-                        {groupDisplayDescription !== "" && (
-                            <div className={getClassName("kcLabelWrapperClass")}>
-                                <label id={`description-${group}`} className={getClassName("kcLabelClass")}>
-                                    {advancedMsg(groupDisplayDescription)}
-                                </label>
-                            </div>
-                        )}
-                    </div>
-                )}
-            </>
-        );
-    }
-
     if (attribute.group?.name !== groupNameRef.current) {
         groupNameRef.current = attribute.group?.name ?? "";
 
diff --git a/src/login/kcContext/KcContext.ts b/src/login/kcContext/KcContext.ts
index 1dd2e286..89963108 100644
--- a/src/login/kcContext/KcContext.ts
+++ b/src/login/kcContext/KcContext.ts
@@ -193,7 +193,7 @@ export declare namespace KcContext {
         profile: {
             attributes: Attribute[];
             attributesByName: Record<string, Attribute>;
-            html5DataAnnotations: Record<string, string>;
+            html5DataAnnotations?: Record<string, string>;
         };
         url: {
             registrationAction: string;
@@ -450,8 +450,8 @@ export declare namespace KcContext {
     export type UpdateUserProfile = Common & {
         pageId: "update-user-profile.ftl";
         profile: {
-            attributes: LegacyAttribute[];
-            attributesByName: Record<string, LegacyAttribute>;
+            attributes: Attribute[];
+            attributesByName: Record<string, Attribute>;
         };
     };
 
@@ -459,8 +459,8 @@ export declare namespace KcContext {
         pageId: "idp-review-user-profile.ftl";
         profile: {
             context: "IDP_REVIEW";
-            attributes: LegacyAttribute[];
-            attributesByName: Record<string, LegacyAttribute>;
+            attributes: Attribute[];
+            attributesByName: Record<string, Attribute>;
         };
     };
 
@@ -517,7 +517,7 @@ export type Attribute = {
         name: string;
         displayDescription?: string;
     };
-    html5DataAnnotations: {
+    html5DataAnnotations?: {
         kcNumberFormat?: string;
         kcNumberUnFormat?: string;
     };
@@ -599,13 +599,6 @@ export type Attribute = {
         | "photo";
 };
 
-export type LegacyAttribute = Omit<Attribute, "group" | "html5DataAnnotations"> & {
-    group: string;
-    groupDisplayHeader?: string;
-    groupDisplayDescription?: string;
-    groupAnnotations: Record<string, string>;
-};
-
 export type Validators = Partial<{
     length: Validators.DoIgnoreEmpty & Validators.Range;
     integer: Validators.DoIgnoreEmpty & Validators.Range;
diff --git a/src/login/kcContext/register.tsx b/src/login/kcContext/register.tsx
new file mode 100644
index 00000000..316c9bce
--- /dev/null
+++ b/src/login/kcContext/register.tsx
@@ -0,0 +1,182 @@
+import { clsx } from "keycloakify/tools/clsx";
+import type { PageProps } from "keycloakify/login/pages/PageProps";
+import { useGetClassName } from "keycloakify/login/lib/useGetClassName";
+import type { KcContext } from "../kcContext";
+import type { I18n } from "../i18n";
+
+export default function Register(props: PageProps<Extract<KcContext, { pageId: "register.ftl" }>, I18n>) {
+    const { kcContext, i18n, doUseDefaultCss, Template, classes } = props;
+
+    const { getClassName } = useGetClassName({
+        doUseDefaultCss,
+        classes
+    });
+
+    const { url, messagesPerField, register, realm, passwordRequired, recaptchaRequired, recaptchaSiteKey } = kcContext;
+
+    const { msg, msgStr } = i18n;
+
+    return (
+        <Template {...{ kcContext, i18n, doUseDefaultCss, classes }} headerNode={msg("registerTitle")}>
+            <form id="kc-register-form" className={getClassName("kcFormClass")} action={url.registrationAction} method="post">
+                <div
+                    className={clsx(
+                        getClassName("kcFormGroupClass"),
+                        messagesPerField.printIfExists("firstName", getClassName("kcFormGroupErrorClass"))
+                    )}
+                >
+                    <div className={getClassName("kcLabelWrapperClass")}>
+                        <label htmlFor="firstName" className={getClassName("kcLabelClass")}>
+                            {msg("firstName")}
+                        </label>
+                    </div>
+                    <div className={getClassName("kcInputWrapperClass")}>
+                        <input
+                            type="text"
+                            id="firstName"
+                            className={getClassName("kcInputClass")}
+                            name="firstName"
+                            defaultValue={register.formData.firstName ?? ""}
+                        />
+                    </div>
+                </div>
+
+                <div
+                    className={clsx(
+                        getClassName("kcFormGroupClass"),
+                        messagesPerField.printIfExists("lastName", getClassName("kcFormGroupErrorClass"))
+                    )}
+                >
+                    <div className={getClassName("kcLabelWrapperClass")}>
+                        <label htmlFor="lastName" className={getClassName("kcLabelClass")}>
+                            {msg("lastName")}
+                        </label>
+                    </div>
+                    <div className={getClassName("kcInputWrapperClass")}>
+                        <input
+                            type="text"
+                            id="lastName"
+                            className={getClassName("kcInputClass")}
+                            name="lastName"
+                            defaultValue={register.formData.lastName ?? ""}
+                        />
+                    </div>
+                </div>
+
+                <div
+                    className={clsx(getClassName("kcFormGroupClass"), messagesPerField.printIfExists("email", getClassName("kcFormGroupErrorClass")))}
+                >
+                    <div className={getClassName("kcLabelWrapperClass")}>
+                        <label htmlFor="email" className={getClassName("kcLabelClass")}>
+                            {msg("email")}
+                        </label>
+                    </div>
+                    <div className={getClassName("kcInputWrapperClass")}>
+                        <input
+                            type="text"
+                            id="email"
+                            className={getClassName("kcInputClass")}
+                            name="email"
+                            defaultValue={register.formData.email ?? ""}
+                            autoComplete="email"
+                        />
+                    </div>
+                </div>
+                {!realm.registrationEmailAsUsername && (
+                    <div
+                        className={clsx(
+                            getClassName("kcFormGroupClass"),
+                            messagesPerField.printIfExists("username", getClassName("kcFormGroupErrorClass"))
+                        )}
+                    >
+                        <div className={getClassName("kcLabelWrapperClass")}>
+                            <label htmlFor="username" className={getClassName("kcLabelClass")}>
+                                {msg("username")}
+                            </label>
+                        </div>
+                        <div className={getClassName("kcInputWrapperClass")}>
+                            <input
+                                type="text"
+                                id="username"
+                                className={getClassName("kcInputClass")}
+                                name="username"
+                                defaultValue={register.formData.username ?? ""}
+                                autoComplete="username"
+                            />
+                        </div>
+                    </div>
+                )}
+                {passwordRequired && (
+                    <>
+                        <div
+                            className={clsx(
+                                getClassName("kcFormGroupClass"),
+                                messagesPerField.printIfExists("password", getClassName("kcFormGroupErrorClass"))
+                            )}
+                        >
+                            <div className={getClassName("kcLabelWrapperClass")}>
+                                <label htmlFor="password" className={getClassName("kcLabelClass")}>
+                                    {msg("password")}
+                                </label>
+                            </div>
+                            <div className={getClassName("kcInputWrapperClass")}>
+                                <input
+                                    type="password"
+                                    id="password"
+                                    className={getClassName("kcInputClass")}
+                                    name="password"
+                                    autoComplete="new-password"
+                                />
+                            </div>
+                        </div>
+
+                        <div
+                            className={clsx(
+                                getClassName("kcFormGroupClass"),
+                                messagesPerField.printIfExists("password-confirm", getClassName("kcFormGroupErrorClass"))
+                            )}
+                        >
+                            <div className={getClassName("kcLabelWrapperClass")}>
+                                <label htmlFor="password-confirm" className={getClassName("kcLabelClass")}>
+                                    {msg("passwordConfirm")}
+                                </label>
+                            </div>
+                            <div className={getClassName("kcInputWrapperClass")}>
+                                <input type="password" id="password-confirm" className={getClassName("kcInputClass")} name="password-confirm" />
+                            </div>
+                        </div>
+                    </>
+                )}
+                {recaptchaRequired && (
+                    <div className="form-group">
+                        <div className={getClassName("kcInputWrapperClass")}>
+                            <div className="g-recaptcha" data-size="compact" data-sitekey={recaptchaSiteKey}></div>
+                        </div>
+                    </div>
+                )}
+                <div className={getClassName("kcFormGroupClass")}>
+                    <div id="kc-form-options" className={getClassName("kcFormOptionsClass")}>
+                        <div className={getClassName("kcFormOptionsWrapperClass")}>
+                            <span>
+                                <a href={url.loginUrl}>{msg("backToLogin")}</a>
+                            </span>
+                        </div>
+                    </div>
+
+                    <div id="kc-form-buttons" className={getClassName("kcFormButtonsClass")}>
+                        <input
+                            className={clsx(
+                                getClassName("kcButtonClass"),
+                                getClassName("kcButtonPrimaryClass"),
+                                getClassName("kcButtonBlockClass"),
+                                getClassName("kcButtonLargeClass")
+                            )}
+                            type="submit"
+                            value={msgStr("doRegister")}
+                        />
+                    </div>
+                </div>
+            </form>
+        </Template>
+    );
+}
diff --git a/src/login/lib/useUserProfileForm.tsx b/src/login/lib/useUserProfileForm.tsx
index a3eef6fa..2e84d34d 100644
--- a/src/login/lib/useUserProfileForm.tsx
+++ b/src/login/lib/useUserProfileForm.tsx
@@ -68,7 +68,7 @@ export type KcContextLike = {
     messagesPerField: Pick<KcContext.Common["messagesPerField"], "existsError" | "get">;
     profile: {
         attributes: Attribute[];
-        html5DataAnnotations: Record<string, string>;
+        html5DataAnnotations?: Record<string, string>;
     };
     passwordRequired: boolean;
     realm: { registrationEmailAsUsername: boolean };
@@ -107,8 +107,7 @@ export function useUserProfileForm(params: ParamsOfUseUserProfileForm): ReturnTy
 
     usePrepareTemplate({
         "styles": [],
-        // NOTE: The ?? {} is for compat with Keycloak version prior to 24
-        "scripts": Object.keys(kcContext.profile.html5DataAnnotations ?? {})
+        "scripts": Object.keys(kcContext.profile?.html5DataAnnotations ?? {})
             .filter(key => key !== "kcMultivalued" && key !== "kcNumberFormat") // NOTE: Keycloakify handles it.
             .map(key => ({
                 "isModule": true,
@@ -126,7 +125,69 @@ export function useUserProfileForm(params: ParamsOfUseUserProfileForm): ReturnTy
     const attributesWithPassword = useMemo(() => {
         const attributesWithPassword: Attribute[] = [];
 
-        for (const attribute of kcContext.profile.attributes) {
+        const attributes = (() => {
+            retrocompat_patch: {
+                if ("profile" in kcContext && "attributes" in kcContext.profile && kcContext.profile.attributes.length !== 0) {
+                    break retrocompat_patch;
+                }
+
+                kcContext.profile = {
+                    "attributes": (["firstName", "lastName", "email", "username"] as const)
+                        .filter(name => (name !== "username" ? true : !kcContext.realm.registrationEmailAsUsername))
+                        .map(name =>
+                            id<Attribute>({
+                                "name": name,
+                                "displayName": id<`\${${MessageKey}}`>(`\${${name}}`),
+                                "required": true,
+                                "value": (kcContext as any).register.formData[name] ?? "",
+                                "html5DataAnnotations": {},
+                                "readOnly": false,
+                                "validators": {},
+                                "annotations": {},
+                                "autocomplete": (() => {
+                                    switch (name) {
+                                        case "email":
+                                            return "email";
+                                        case "username":
+                                            return "username";
+                                        default:
+                                            return undefined;
+                                    }
+                                })()
+                            })
+                        ),
+                    "html5DataAnnotations": {}
+                };
+            }
+
+            return kcContext.profile.attributes;
+        })();
+
+        for (const attribute_pre_group_patch of attributes) {
+            const attribute = (() => {
+                if (typeof attribute_pre_group_patch.group === "string" && attribute_pre_group_patch.group !== "") {
+                    const { group, groupDisplayHeader, groupDisplayDescription, groupAnnotations, ...rest } =
+                        attribute_pre_group_patch as Attribute & {
+                            group: string;
+                            groupDisplayHeader?: string;
+                            groupDisplayDescription?: string;
+                            groupAnnotations: Record<string, string>;
+                        };
+
+                    return id<Attribute>({
+                        ...rest,
+                        "group": {
+                            "name": group,
+                            "displayHeader": groupDisplayHeader,
+                            "displayDescription": groupDisplayDescription,
+                            "html5DataAnnotations": {}
+                        }
+                    });
+                }
+
+                return attribute_pre_group_patch;
+            })();
+
             attributesWithPassword.push(attribute);
 
             add_password_and_password_confirm: {
@@ -191,7 +252,6 @@ export function useUserProfileForm(params: ParamsOfUseUserProfileForm): ReturnTy
                         apply_formatters: {
                             const { attribute } = formFieldState;
 
-                            // NOTE: The `?? {}` is for compat with Keycloak version prior to 24
                             const { kcNumberFormat } = attribute.html5DataAnnotations ?? {};
 
                             if (kcNumberFormat === undefined) {
@@ -407,7 +467,6 @@ function useGetErrors(params: { kcContext: Pick<KcContextLike, "messagesPerField
                 let { valueOrValues } = formFieldState;
 
                 unFormat_number: {
-                    // NOTE: The `?? {}` is for compat with Keycloak version prior to 24
                     const { kcNumberUnFormat } = attribute.html5DataAnnotations ?? {};
 
                     if (kcNumberUnFormat === undefined) {
@@ -791,7 +850,6 @@ function useGetErrors(params: { kcContext: Pick<KcContextLike, "messagesPerField
                         assert(typeof valueOrValues === "string");
 
                         unFormat_number: {
-                            // NOTE: The `?? {}` is for compat with Keycloak version prior to 24
                             const { kcNumberUnFormat } = attribute.html5DataAnnotations ?? {};
 
                             if (kcNumberUnFormat === undefined) {