Is it permissible to donate money or give charity when the Imam requests it while on the minbar?

As long as the fundraising occurred before the start of the sermon (khutbah (definition)), there is no objection to it, and it is considered cooperation in righteousness and piety. The Prophet, peace and blessings be upon him, commanded charity and collected for it before his sermon, and he saw his face light up with joy because of it. However, it would have been better to postpone collecting donations until after the prayer to avoid stepping over people's necks, which is prohibited once the preacher is seated on the minbar.