Dear Masters,
Given this files ('file.txt') how can I use a compact regex to clean it so that from this: 
<h3>Warning</h3><blockquote><FONT SIZE=+1 color=#aa0000><B>
Circular contig    NC_001224.1    leftmost feature    0    Q0050    le
+ft neighbour    Q0275
</B></FONT></blockquote><BR><HR SIZE=3>
<h3>Warning</h3><blockquote><FONT SIZE=+1 color=#aa0000><B>
Circular contig    NC_001224.1    rightmost feature    18    Q0275    
+right neighbour    Q0045
</B></FONT></blockquote><BR><HR SIZE=3>
>YJR152W|DAL5
TGATTTTGGATATTCATCAAAGGAAACCCTATTAATGGGTTTACCTACAGGTGCTGTTGA
ATTGGTAGGTTGTCCACTTTTTGGTATTCTAGCAGTTTATGCAGCCAATAAGAAGATACC
ATTTTGGAAATATAAGTTGAGTTGGGCTATTTTTGCAGCTGTCTTAGCATTGATTGCTAG
CTGCATGTTAGGGTTTGCAACAAACTCCAAAAAAGCAAGACTGGCTGGTGCTTACCTGTG
GTACATCTCGCCCGTCTCATTTATTTGCGTACTTTCCAATATCAGTGCGAATTCCTCGGG
ATATAGTAAAAAATGGACTGTATCTTCAATAAACTTAGTAGCATATGCTGCAGCTAACTT
GGCAGGACCACAAACCTTTATTGCTAAGCAGGCTCCTAAATATCATGGCGCTAAGGTCGC
TATGGTCGTATGTTATGCTGTTATGATCGTGCTTCTATCTATACTGCTCATCGTCAATTT
AAGGGAAAACAAGAGACGTGATAAGATAGCTGCCGAGAGAGGGTTCCCTGAAGAAACAGA
GAATTTAGAGTTTTCTGATTTGACTGATTTTGAAAATCCAAATTTCAGATACACTTTATG
>YKR039W|GAP1
CCTAGCTGAACAGAGATTTCTGCCAGAAATCTTTTCCTACGTTGACCGTAAGGGTAGACC
ATTGGTGGGAATTGCTGTCACATCTGCATTCGGTCTTATTGCGTTTGTTGCCGCCTCCAA
AAAGGAAGGTGAAGTTTTCAACTGGTTACTAGCCTTGTCTGGGTTGTCATCTCTATTCAC
ATGGGGTGGTATCTGTATTTGTCACATTCGTTTCAGAAAGGCATTGGCCGCCCAAGGAAG
AGGCTTGGATGAATTGTCTTTCAAGTCTCCTACCGGTGTTTGGGGTTCCTACTGGGGGTT
ATTTATGGTTATTATTATGTTCATTGCCCAATTCTACGTTGCTGTATTCCCCGTGGGAGA
TTCTCCAAGTGCGGAAGGTTTCTTCGAAGCTTATCTATCCTTCCCACTTGTTATGGTTAT
GTACATCGGACACAAGATCTATAAGAGGAATTGGAAGCTTTTCATCCCAGCAGAAAAGAT
GGACATTGATACGGGTAGAAGAGAAGTCGATTTAGATTTGTTGAAACAAGAAATTGCAGA
AGAAAAGGCAATTATGGCCACAAAGCCAAGATGGTATAGAATCTGGAATTTCTGGTGTTA
;WARNING    invalid query foo
;WARNING    invalid query bar
;WARNING    invalid query qux

[download]
we get simply: 
>YJR152W|DAL5
TGATTTTGGATATTCATCAAAGGAAACCCTATTAATGGGTTTACCTACAGGTGCTGTTGA
ATTGGTAGGTTGTCCACTTTTTGGTATTCTAGCAGTTTATGCAGCCAATAAGAAGATACC
ATTTTGGAAATATAAGTTGAGTTGGGCTATTTTTGCAGCTGTCTTAGCATTGATTGCTAG
CTGCATGTTAGGGTTTGCAACAAACTCCAAAAAAGCAAGACTGGCTGGTGCTTACCTGTG
GTACATCTCGCCCGTCTCATTTATTTGCGTACTTTCCAATATCAGTGCGAATTCCTCGGG
ATATAGTAAAAAATGGACTGTATCTTCAATAAACTTAGTAGCATATGCTGCAGCTAACTT
GGCAGGACCACAAACCTTTATTGCTAAGCAGGCTCCTAAATATCATGGCGCTAAGGTCGC
TATGGTCGTATGTTATGCTGTTATGATCGTGCTTCTATCTATACTGCTCATCGTCAATTT
AAGGGAAAACAAGAGACGTGATAAGATAGCTGCCGAGAGAGGGTTCCCTGAAGAAACAGA
GAATTTAGAGTTTTCTGATTTGACTGATTTTGAAAATCCAAATTTCAGATACACTTTATG
>YKR039W|GAP1
CCTAGCTGAACAGAGATTTCTGCCAGAAATCTTTTCCTACGTTGACCGTAAGGGTAGACC
ATTGGTGGGAATTGCTGTCACATCTGCATTCGGTCTTATTGCGTTTGTTGCCGCCTCCAA
AAAGGAAGGTGAAGTTTTCAACTGGTTACTAGCCTTGTCTGGGTTGTCATCTCTATTCAC
ATGGGGTGGTATCTGTATTTGTCACATTCGTTTCAGAAAGGCATTGGCCGCCCAAGGAAG
AGGCTTGGATGAATTGTCTTTCAAGTCTCCTACCGGTGTTTGGGGTTCCTACTGGGGGTT
ATTTATGGTTATTATTATGTTCATTGCCCAATTCTACGTTGCTGTATTCCCCGTGGGAGA
TTCTCCAAGTGCGGAAGGTTTCTTCGAAGCTTATCTATCCTTCCCACTTGTTATGGTTAT
GTACATCGGACACAAGATCTATAAGAGGAATTGGAAGCTTTTCATCCCAGCAGAAAAGAT
GGACATTGATACGGGTAGAAGAGAAGTCGATTTAGATTTGTTGAAACAAGAAATTGCAGA
AGAAAAGGCAATTATGGCCACAAAGCCAAGATGGTATAGAATCTGGAATTTCTGGTGTTA

[download]
In principle we want to:

---
neversaint and everlastingly indebted.......

In reply to Cleaning up a text file with compact regex by neversaint

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