i'm glad you're gonna be more active :)))
there are a lot of potential triggers, and a lot of people have their specific triggers in their bios, but ones to always keep in mind are (obvious tw for the following list)
Su*c*de
D*ath
Ab*se
R*pe
Ass*ult/v*olence
W*apons like g*ns, kn*ves, etc
S*lf h*rm
F*mily and specific f*mily members
Sch**l
E*ting d*sorders
D*pression, anx*ety, p*nic att*cks
Disturbing images
G*re
B*dy h*rror
Bl**d and n*edles
S*xual and nsfw things like k*nks
G*nitalia and b*dy parts/functions
R*cism
H*m*ph*bia/tr*nsph*bia/general q***rphobia
B*llying
Sl*rs
Abl**sm
D*sph*ria
P*litics
Gr**ming
General negativity
P*lice
Dr*gs
Alc*h*l
H*spitals
D*ssociation, age r*gress*ion
F*re
N*tural d*sasters
B*gs
Controversial people, identities
N*zis
All caps