getAttributeKeyHandle() on null Exception with Member Advanced Search

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Go to Search Users (/dashboard/users/search), click "Advanced" in search field. The activity indicator won't stop and you see the exception like below in Logs page.
Exception Occurred: .../concrete5-8.4.3/concrete/src/Search/Column/AttributeKeyColumn.php:16 Call to a member function getAttributeKeyHandle() on null (0)


Status: New

concrete5 Environment Information

# concrete5 Version
Core Version - 8.4.3
Version Installed - 8.4.3
Database Version - 20180716000000

# concrete5 Packages
Cycle2 Slide Show (1.0.2), Migration Tool (0.9.0), Page Redirect (2.0), Page Selector Attribute (2.0), PDF Renderer (1.0.0), Spacer (0.9.4), Stucco (2.1.6)

# concrete5 Overrides
blocks/search/view.php, blocks/search, themes/images/bg-block.gif, themes/images/bg-stripe.png, themes/images/icon_doc.gif, themes/images/icon_pdf.gif, themes/images/icon_ppt.gif, themes/images/icon_xls.gif, themes/images, themes/js/original.js, themes/js

# concrete5 Cache Settings
Block Cache - On
Overrides Cache - On
Full Page Caching - On - If blocks on the particular page allow it.
Full Page Cache Lifetime - Every 6 hours (default setting).

# Server Software
Apache

# Server API
apache2handler

# PHP Version
7.2.10

# PHP Extensions
apache2handler, apcu, Core, ctype, curl, date, dom, exif, fileinfo, filter, gd, gettext, gmp, hash, iconv, imagick, intl, json, libxml, mbstring, mcrypt, mysqli, mysqlnd, openssl, pcre, PDO, pdo_mysql, pdo_sqlite, Phar, posix, Reflection, session, SimpleXML, snmp, soap, SPL, sqlite3, standard, tokenizer, xml, xmlreader, xmlwriter, xsl, Zend OPcache, 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 - -1
max_input_vars - 1000
memory_limit - 128M
post_max_size - 8M
upload_max_filesize - 2M
mysqli.max_links - Unlimited
mysqli.max_persistent - Unlimited
pcre.backtrack_limit - 1000000
pcre.recursion_limit - 100000
session.cache_limiter - <i>no value</i>
session.gc_maxlifetime - 7200
soap.wsdl_cache_limit - 5
opcache.max_accelerated_files - 10000
opcache.max_file_size - 0
opcache.max_wasted_percentage - 5

Browser User-Agent String

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:63.0) Gecko/20100101 Firefox/63.0