#63 Comment doesn't post after new tab opened

Background

When commenting I usually open up other tabs to search for content to add link to a content in that comment. However, when I open a new tab for anything and try to post a comment on previous tab it causes it not to post and it shows this on terminal:

Traceback (most recent call last):
  File "/path/to/FastLBRY-GTK/flbry/comments.py", line 634, in send_do
    send_comment(win, message, claim_id, tb, support=support_bid_entry)
  File "/path/to/Codes/FastLBRY-GTK/flbry/comments.py", line 788, in send_comment
    sigs = sign(message, channel_name)
  File "/path/to/Codes/FastLBRY-GTK/flbry/comments.py", line 849, in sign
    raise ValueError("Must give either data or hexdata")
ValueError: Must give either data or hexdata

Posting comment only in the last opened tab works. If the latest opened tab is closed posting comment on no tab works other than reloading the video.

Tested on 6a34355fda

Steps to reproduce

1. Open a video
2. Open something in a new tab (for example, middle-clicking the channel name)
3. Come back to the video tab opened first
4. Try to post a comment

Expected result

Post the comment (and clear the form)

Current result

Does not post the comment (and comment form stays as it is)

Workaround

Since there is no reload option...

On the video tab on which the comment is being posted:

• Copy the comment text and keep it in a text editor or somewhere
• Go to Details tab, click on lbry:// URL beside "LBRY URL:" and copy it
• Paste on search bar above and press enter
• Copy the comment text and post comment

Hm... Probably due to tabs being an afterthought implemented very fast. Perhaps some of the comments code still thinks that there is only one tab in the program.

Here are Tabs related commits:

3226f5babb

ccc5994446

728ab3d3bf

6e14b413ab

a5b55e1495