This may be a plugin or theme conflict. Please attempt to disable all plugins, and use one of the default (Twenty*) themes. If the problem goes away, enable them one by one to identify the source of your troubles.
If you can install plugins, install “Health Check”: https://ww.wp.xz.cn/plugins/health-check/ On the troubleshooting tab, you can click the button to disable all plugins and change the theme for you, while you’re still logged in, without affecting normal visitors to your site. You can then use its admin bar menu to turn on/off plugins and themes one at a time.
See http://www.wpbeginner.com/plugins/how-to-deactivate-all-plugins-when-not-able-to-access-wp-admin/
Thread Starter
esh4646
(@eshexpress)
Thanks for the suggestion.
I installed and activated a twenty twenty, and created a new post named “trial”. The problem was gone away with twenty twenty theme. However, after turning back to my pro theme, that post named “trial” gave the same error: the first letter was a huge one.
So, does it mean this problem is related to my pro theme? And lastly, can it be fixed by the theme developers or WordPress, etc.?
Thanks.
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This reply was modified 4 years, 9 months ago by
esh4646.
Yes, then this is an issue with your theme. Please contact its developers.
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