Praise be to Allah, and may blessings and peace be upon the Messenger of Allah. To proceed:
The Prophet ﷺ used to seek refuge in Allah during his prayer from the trial of life and death and the trial of the Messiah, the Dajjal, as mentioned in the authentic hadith narrated from Aishah رضي الله عنها.
It refers to the trials that a person is exposed to during his lifetime, such as the trials of desires, doubts, sins, and religious innovations, which may even lead to disbelief and misguidance. Among the greatest of these trials is for a person to become attached to worldly life and become distracted by it from the Hereafter, or to develop doubts about what the Messenger ﷺ brought.
This includes what a person may be exposed to during his final moments and as death approaches, such as Satan's attempt to mislead him and turn him away from the truth. It also includes the trial of the grave, where a person is questioned about his Lord, his religion, and his Prophet ﷺ.
For this reason, the Prophet ﷺ used to seek refuge in Allah from these trials because of the great danger they pose to a person's religion and his final outcome.
It is among the greatest trials to occur on the face of the earth. The Prophet ﷺ informed us that it is the greatest trial from the creation of Adam until the establishment of the Hour. Therefore, he warned his Ummah against it and instructed them to seek refuge in Allah from it.
As for claiming that democracy is part of the trial of the Dajjal, there is no evidence for this, and it is not correct to link democracy to the trial of the Dajjal in this manner, regardless of the Islamic ruling concerning democracy itself. The ruling on democracy is one matter, while the trial of the Messiah, the Dajjal, is another.
Not every error, evil, or deviation should be attributed to the trial of the Dajjal. It is not correct to force matters into the subject of his trial when there is no evidence for them in the relevant texts.
And Allah تعالى knows best.