Repeatedly disconnected "due to inactivity" randomly after any? action

From directus created by rmNyro : directus/directus#2022

Hi,

Long story short, I came to work today and I had that annoying bug which kicks me almost randomly "due to inactivity". I managed to check the timer but the value is 120 and changing it doesn't do a thing... Yesterday I did some automated (~130 entry added) import through the api. Worked like a charm, no problem whatsoever.

Today I needed to check something in the interface before testing bigger imports. I didn't do anything else than enter login/pass and connect. Then I instantly got kicked. I can (with a little bit of luck) connect if the redirection takes me to settings apparently (EDIT: the "safe domains" extended after the db reboot). Then when I try to change some permissions or see any tables, I get disconnected instantly or almost instantly after that (EDIT: now I have ~50% to see a category page).

Context

PHP: 7.0.23 Mysql: MariaDB 10.1 Web server: Apache OS: Debian 8.9

Complementary information

I was curious if this was related somehow to the update you made (it was unlikely to be so but it's a test server) so I followed your upgrade guide and here are the commands I ended up using:

cd tmp && rm -rf ./* \
&& tar -xzf ../directus-build-6.4.5-20171218214444.tar.gz \
&& rm -rf ../app/ ../assets/ ../bin/ ../composer.* ../customs/ ../index.php ../installation/ ../login.php ../readme.md ../templates/ ../thumbnail/ ../vendor/ \
&& mv app/ assets/ bin/ composer.* customs/ index.php installation/ login.php readme.md templates/ thumbnail/ vendor/ ../

I did launch php bin/directus db:upgrade after that and got:

db:setup - table 'directus_schema_migrations' already exists. Nothing to do.
db:migrate - UpdateDirectusUsersTokenColumn - Error executing 'query' with:
ALTER TABLE `directus_users` CHANGE `token` `token` varchar(128) NOT NULL

Reason: Duplicate entry '' for key 'directus_users_token_unique'

But it didn't break the site nor did it fix the bug (no change so far, as expected).

I'm absolutely clueless right now. I'll try to investigate further...maybe it's something real dumb... Tell me what you info need and I'll see if I can collect it.