komakoma

8.5.4ファイルマネージャーで「属性」にエラーが出ます

ファイルマネージャーで画像をアップロードするとエラーになります。
画像はアップロードできているのですが、エラーの文字、アップロードし終わった際に出る小窓下部「属性」の箇所に以下エラー分文が出ます。

原因がおわかりになる方がいらっしゃいましたら、お知恵を貸してください。
どうぞよろしくおねがいいたします。

▼出るエラー　※アップロードした画像すべてにこのエラーが出ています
{"error":{"type":"Whoops\\Exception\\ErrorException","message":"Cannot declare class Concrete\\Theme\\Elemental\\PageTheme, because the name is already in use","file":"\/home\/httpd\/web-root\/www\/application\/themes\/elemental\/page_theme.php","line":7,"trace":[{"file":"\/home\/httpd\/web-root\/www\/application\/themes\/elemental\/page_theme.php","line":7,"function":null,"class":"Whoops\\Exception\\ErrorException","args":["Cannot declare class Concrete\\Theme\\Elemental\\PageTheme, because the name is already in use"]},{"file":"\/home\/httpd\/web-root\/www\/concrete\/vendor\/filp\/whoops\/src\/Whoops\/Run.php","line":433,"function":"handleError","class":"Whoops\\Run","args":[64,"Cannot declare class Concrete\\Theme\\Elemental\\PageTheme, because the name is already in use","\/home\/httpd\/web-root\/www\/application\/themes\/elemental\/page_theme.php",7]},{"file":"[internal]","line":0,"function":"handleShutdown","class":"Whoops\\Run","args":[]}]},"errors":["Cannot declare class Concrete\\Theme\\Elemental\\PageTheme, because the name is already in use"]}



▼環境
# concrete5 Version
Core Version - 8.5.4
Version Installed - 8.5.4
Database Version - 20200609145307

# Database Information
Version: 5.5.60-MariaDB
SQL Mode:

# concrete5 Cache Settings
Block Cache - On
Overrides Cache - On
Full Page Caching - Off
Full Page Cache Lifetime - Every 6 hours (default setting).

# Server Software
Apache/2.4.6 (CentOS) OpenSSL/1.0.2k-fips PHP/7.2.13

# Server API
apache2handler

# PHP Version
7.2.13

# PHP Extensions
apache2handler, apcu, bcmath, bz2, calendar, Core, ctype, curl, date, dom, exif, fileinfo, filter, ftp, gd, gettext, gmp, hash, iconv, intl, json, libxml, mbstring, mcrypt, mysqli, mysqlnd, openssl, pcre, PDO, pdo_mysql, pdo_sqlite, Phar, posix, recode, Reflection, session, shmop, SimpleXML, soap, sockets, SPL, sqlite3, standard, sysvmsg, sysvsem, sysvshm, tokenizer, wddx, xml, xmlreader, xmlrpc, xmlwriter, xsl, zip, zlib

# PHP Settings
max_execution_time - 30
log_errors_max_len - 1024
max_file_uploads - 20
max_input_nesting_level - 64
max_input_time - 60
max_input_vars - 10000
memory_limit - 128M
post_max_size - 100M
upload_max_filesize - 100M
mysqli.max_links - Unlimited
mysqli.max_persistent - Unlimited
pcre.backtrack_limit - 1000000
pcre.recursion_limit - 100000
session.cache_limiter - no value
session.gc_maxlifetime - 7200
soap.wsdl_cache_limit - 5