Ok I tried to disable each of the extensions from the interface and nothing changes.
U_U
https://i.imgur.com/DT4cV3x.jpg
Here is the list of my extensions:
# composer show
Do not run Composer as root/super user! See https://getcomposer.org/root for details
amaurycarrade/flarum-ext-syndication v0.1.5 Brings RSS and Atom feeds to Flarum
avatar4eg/flarum-ext-users-list 0.1.1 Add users list in admin panel.
clarkwinkelmann/flarum-ext-emojionearea 0.1.2 Add EmojiOne Area emoji picker to Flarum
components/font-awesome 4.7.0 The iconic font designed for use with Twitter Bootstrap.
danielstjules/stringy 1.10.0 A string manipulation library with multibyte support
davis/flarum-ext-securehttps 0.1.0-beta5 Changes all images using http to https
dflydev/fig-cookies v1.0.2 Cookies for PSR-7 HTTP Message Interface.
doctrine/annotations v1.4.0 Docblock Annotations Parser
doctrine/cache v1.6.2 Caching library offering an object-oriented API for many cache backends
doctrine/collections v1.4.0 Collections Abstraction library
doctrine/common v2.7.3 Common Library for Doctrine projects
doctrine/dbal v2.5.13 Database Abstraction Layer
doctrine/inflector v1.2.0 Common String Manipulations with regard to casing and singular/plural rules.
doctrine/lexer v1.0.1 Base library for a lexer that can be used in Top-Down, Recursive Descent Parsers.
filp/whoops 2.1.14 php error handling for cool kids
flagrow/ads 0.1.0-beta.4 Bombarding your users with ads everywhere, if you want..
flagrow/flarum-ext-analytics 0.6.0 Tracks analytics using googles and piwik metric tool analytics
flagrow/upload 0.6.0 The file upload extension for the Flarum forum with insane intelligence.
flarum/core v0.1.0-beta.7 Delightfully simple forum software.
flarum/flarum-ext-akismet v0.1.0-beta.6 Stop spam using the Akismet anti-spam service.
flarum/flarum-ext-approval v0.1.0-beta.7 Make discussions and posts require moderator approval.
flarum/flarum-ext-auth-facebook v0.1.0-beta.6 Allow users to log in with Facebook.
flarum/flarum-ext-auth-github v0.1.0-beta.6 Allow users to log in with GitHub.
flarum/flarum-ext-auth-twitter v0.1.0-beta.6 Allow users to log in with Twitter.
flarum/flarum-ext-bbcode v0.1.0-beta.5 Allow posts to be formatted with BBCode.
flarum/flarum-ext-emoji v0.1.0-beta.6 Convert text and unicode emoji into Twemoji.
flarum/flarum-ext-english v0.1.0-beta.7 English language pack.
flarum/flarum-ext-flags v0.1.0-beta.7 Allow users to flag posts for moderator review.
flarum/flarum-ext-likes v0.1.0-beta.6 Allow users to like posts.
flarum/flarum-ext-lock v0.1.0-beta.7 End a discussion and don't let anyone add further replies.
flarum/flarum-ext-markdown v0.1.0-beta.5 Allow posts to be formatted with Markdown.
flarum/flarum-ext-mentions v0.1.0-beta.7 Mention and reply to specific posts and users.
flarum/flarum-ext-pusher v0.1.0-beta.6 See new discussions and posts in real-time using Pusher.
flarum/flarum-ext-sticky v0.1.0-beta.7 Pin discussions to the top of the list.
flarum/flarum-ext-subscriptions v0.1.0-beta.6 Allow users to follow discussions and receive notifications for new posts.
flarum/flarum-ext-suspend v0.1.0-beta.7 Suspend users so they can't post.
flarum/flarum-ext-tags v0.1.0-beta.8 Organize discussions into a hierarchy of tags and categories.
franzl/studio 0.11.2 Develop your Composer libraries with style
franzl/whoops-middleware 0.4.1
ganuonglachanh/flarum-ext-search 0.3 Allows to search by discusstion title
google/recaptcha 1.1.3 Client library for reCAPTCHA, a free service that protect websites from spam and abuse.
guzzlehttp/guzzle 6.3.0 Guzzle is a PHP HTTP client library
guzzlehttp/promises v1.3.1 Guzzle promises library
guzzlehttp/psr7 1.4.2 PSR-7 message implementation that also provides common utility methods
http-interop/http-middleware 0.2.0 Common interface for HTTP middleware
illuminate/bus v5.1.41 The Illuminate Bus package.
illuminate/cache v5.1.41 The Illuminate Cache package.
illuminate/config v5.1.41 The Illuminate Config package.
illuminate/container v5.1.41 The Illuminate Container package.
illuminate/contracts v5.1.41 The Illuminate Contracts package.
illuminate/database v5.1.41 The Illuminate Database package.
illuminate/events v5.1.41 The Illuminate Events package.
illuminate/filesystem v5.1.41 The Illuminate Filesystem package.
illuminate/hashing v5.1.41 The Illuminate Hashing package.
illuminate/mail v5.1.41 The Illuminate Mail package.
illuminate/pipeline v5.1.41 The Illuminate Pipeline package.
illuminate/support v5.1.41 The Illuminate Support package.
illuminate/validation v5.1.41 The Illuminate Validation package.
illuminate/view v5.1.41 The Illuminate View package.
intervention/image 2.4.1 Image handling and manipulation library with support for Laravel integration
ircmaxell/random-lib v1.2.0 A Library For Generating Secure Random Numbers
ircmaxell/security-lib v1.1.0 A Base Security Library
johnhearfield/flarum-ext-oauth-google v0.1.0-beta.8.1 Allow users to log in with Google.
league/flysystem 1.0.41 Filesystem abstraction: Many filesystems, one API.
league/oauth1-client 1.7.0 OAuth 1.0 Client Library
league/oauth2-client 1.4.2 OAuth 2.0 Client Library
league/oauth2-facebook 1.4.5 Facebook OAuth 2.0 Client Provider for The PHP League OAuth2-Client
league/oauth2-github 0.2.2 Github OAuth 2.0 Client Provider for The PHP League OAuth2-Client
league/oauth2-google 1.0.1 Google OAuth 2.0 Client Provider for The PHP League OAuth2-Client
matthiasmullie/minify 1.3.56 CSS & JavaScript minifier, in PHP. Removes whitespace, strips comments, combines files (incl. @import statements and small assets in CSS files), and optimizes/shortens a few c...
matthiasmullie/path-converter 1.1.0 Relative path converter
milescellar/flarum-ext-french v1.1.0 French language pack for Flarum.
monolog/monolog 1.23.0 Sends your logs to files, sockets, inboxes, databases and various web services
nesbot/carbon 1.22.1 A simple API extension for DateTime.
nikic/fast-route v0.6.0 Fast request router for PHP
oyejorge/less.php v1.7.0.14 PHP port of the Javascript version of LESS http://lesscss.org (Originally maintained by Josh Schmidt)
paragonie/random_compat v1.4.2 PHP 5.x polyfill for random_bytes() and random_int() from PHP 7
psr/http-message 1.0.1 Common interface for HTTP messages
psr/log 1.0.2 Common interface for logging libraries
pusher/pusher-php-server 2.6.4 Library for interacting with the Pusher REST API
ramsey/uuid 3.7.1 Formerly rhumsaa/uuid. A PHP 5.4+ library for generating RFC 4122 version 1, 3, 4, and 5 universally unique identifiers (UUID).
s9e/flarum-ext-mediaembed 0.3.2 Embed third-party content in your Flarum.
s9e/text-formatter 0.8.5 Multi-purpose text formatting and markup library. Plugins offer support for BBCodes, Markdown, emoticons, HTML, embedding media (YouTube, etc...), enhanced typography and more.
samdark/sitemap 2.1.0 Sitemap and sitemap index builder
sijad/flarum-ext-links 0.1.0-beta.6 Manage flarum primary navbar menu links.
sijad/flarum-ext-pages 0.1.0-beta.3 Create custom page with Flarum
sijad/flarum-ext-recaptcha 0.0.2 Google reCAPTCHA for flarum
swiftmailer/swiftmailer v5.4.8 Swiftmailer, free feature-rich PHP mailer
symfony/console v2.8.31 Symfony Console Component
symfony/debug v2.7.38 Symfony Debug Component
symfony/filesystem v3.3.13 Symfony Filesystem Component
symfony/finder v2.7.38 Symfony Finder Component
symfony/http-foundation v2.7.38 Symfony HttpFoundation Component
symfony/polyfill-mbstring v1.6.0 Symfony polyfill for the Mbstring extension
symfony/process v3.3.13 Symfony Process Component
symfony/translation v2.7.38 Symfony Translation Component
symfony/yaml v2.8.31 Symfony Yaml Component
terabin/flarum-ext-sitemap v1.0.2-beta.2 Generate a Sitemap for Flarum automatically
tijsverkoyen/akismet 1.1.1 Akismet is a wrapper-class to communicate with the Akismet API.
tobscure/json-api v0.3.0 JSON-API responses in PHP
wiwatsrt/flarum-ext-best-answer v0.1.0-beta.11 Best Answer for Flarum.
xengine/flarum-ext-markdown-editor 1.3.1 WYSIWYG Editor for Flarum
zendframework/zend-diactoros 1.6.1 PSR HTTP Message implementations
zendframework/zend-escaper 2.5.2
zendframework/zend-stratigility 1.3.3 Middleware for PHP
zeokat/flarum-ext-seoslugs v0.1.1 Use friendly URLs (aka transliteration) in slugs
I confirm that this behaviour occurs ALL TIME.
Whether for the creation of a topic or in a reply
Another interesting point is to see an Apache 429 error.
193.252.149.197 - - [02/Mar/2017:22:53:29 +0100] "POST /api/discussions HTTP/1.1" 429 459 "https://deepin-fr.org/t/admin" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
193.252.149.197 - - [02/Mar/2017:22:54:32 +0100] "POST /api/posts HTTP/1.1" 429 459 "https://deepin-fr.org/d/367-nouveau-sur-deepin" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:62.0) Gecko/20100101 Firefox/62.0"
I tried also to increase KeepAliveTimeOut
grep -i alive /etc/apache2/apache2.conf |grep -v ^#
KeepAlive On
MaxKeepAliveRequests 100
KeepAliveTimeout 15
But still occur U_U